When the Cold War ended in 1991 and Russian archives were opened for a while a lot of mysteries were revealed. Some revelations still cause problems, not because so many myths were disproved but because about the same time the Internet came along and made it much more difficult keep secrets or create false realities and maintain them in the future. Thus Russia and China, as well as traditionally the more open societies in the West, could not revive the useful (for all governments) secrecy and control of information that reached a peak in the 20th century. It was the reach and control of pre-Internet mass media that made so many corrupt and murderous dictatorships possible. A few are still trying to hang on, but that proves difficult in an age of instant worldwide communications that cannot to controlled.by a few.
The opening of the Soviet archives documented how crucial it was for a tyrant to declare any military information a state secret and enforce those rules. This was especially true when it came to revealing how ineffective their armed forces actually were, past and present and future. Thus until the Cold War ended the true extent of the World War II casualties Russia suffered (nearly 30 million dead) was considered a state secret and the number admitted to was less than half the real one. The extent to which corruption and government incompetence played a major role in causing Russian economic failure and military defeats also became known in excruciating detail. For example the archives revealed that the Russians, not the Chinese, ordered and enabled North Korea to invade the south in 1950. Chinese sources confirmed this once the Internet and mass access reached China. It made it clear the Chinese had always resented being dragged into a costly “Russian war.” This version of the Korean War undermines the authority of the current Kim dynasty that has ruled the north since 1945 and desperately clings to power in an age where tyrants can’t hide their misdeeds. The Kims tried to keep cell phones and Internet out and were relatively successful. But like a small breach in a massive dam the details of their misdeeds got in and caused the police state to crumble from top to bottom. For example by 2016 more and more North Korean university students were bribing their way out of mandatory participation in major “patriotic holiday” celebrations. This came as a shock to the government because eventually these university students would run the police state but if they don’t believe in the Kim version of history will the Kims still be in charge? China doubts it and most Chinese have already made clear to their own communist (but no longer socialist) rulers that this applies to everyone. The current Chinese rulers are trying to deal with reality while the Kims are trying to ignore it. And anyone with access to the Internet (which have the world population now has) can follow the drama in real time.
Other revelations from the Moscow archives revealed that the Soviets had already created schemes that were indeed stranger than fiction. These included a plan to move saboteurs from Nicaragua across the Mexican border and into the U.S. disguised as illegal aliens. Radar stations, pipelines and power towers were all targeted in great detail as were port facilities in places like New York City. Other archive documents, available to researchers for a few years in the early 1990s (when a fistful of hundred dollar bills could work wonders) delivered all manner of disturbing and now well documented proofs. The Rosenbergs were indeed Russian spies, Alger Hiss was mixed up in Russian espionage efforts and the American Communist Party was in the pay of the Soviet Union and served as a tool for espionage, subversion and propaganda. Many left wing writers and politicians were either on the Soviet payroll, or eager to assist Soviet espionage activities.
With all this information it became possible to more accurately assess the nature, extent and effectiveness of communist era espionage. The Soviets didn't really invent anything new but they energetically improved upon ancient techniques and thus made the 20th century a golden age for spying. Basically, the Russians realized that successful spying was all about developing a lot of personal relationships, and then exploiting as many as possible. Early on, in the 1920s and 30s, the Soviets had a lot of capable and eager agents. And there were many communist sympathizers worldwide. Thousands of these pro-Communists were turned into valuable Soviet agents. Those that got caught were declared "martyrs" or, if possible, persecuted patriots of their home countries. Nothing was wasted.
Also revealed was proof that Stalin's purges in the late 1930s brought this golden age to an end. Most of the excellent Soviet agents were executed. Many of the foreign spies began to have second thoughts about working for the Soviet Union. But then World War II came along and made recruiting spies easier for a time. This continued for a while after World War II. But without the large number of skilled and loyal true believers some new enticements were used. The most frequently used ploy was to threaten the safety of relatives behind the Iron Curtain. Western counterintelligence soon caught on to this, and having relatives back in the old country kept a lot of people from getting security clearances or sensitive jobs.
But the Soviets had many more techniques they could use. Sex and blackmail (often used together) were very successful. Attractive men and women were recruited, trained and sent forth to be romantic for the revolution. This worked particularly well in West Germany, where East German spy studs recruited a number of key female staff in NATO and West German organizations. By the 1970s, the Soviets were frequently using the most basic of all enticements; money. This worked quite well, and until the end of the Cold War Western nations refused to realize how successful this approach could be. We also underestimated how many secrets could be uncovered by simply collecting all the information freely available in a democracy. In the last two decades of the Soviet Union its spies were increasingly successful in obtaining valuable information this way, but telling their bosses it was really from well-placed spies. The spymasters in Moscow never caught on to this little deception or didn't care as long as the good stuff kept coming back to Moscow.
Other nations have since developed new angles that are, in some ways, superior to the Soviet innovations and refinements. China, for example, has had large overseas populations for centuries. These "overseas Chinese" usually did not assimilate completely and retained considerable loyalty, and family connections, with the homeland. For many decades after World War II, most overseas Chinese were either anti-communist or reluctant to get involved with Chinese politics. But once China began economic reforms in the 1970s this changed. It was OK to visit China, and to receive Chinese officials in America. This was China's espionage opportunity.
While the Russians had few agents who could pass for Americans, and operate freely in the U.S., China's spies could get away with just being Chinese. They used the soft sell, realizing that by collecting small bits of information from many people, most of whom did not even consider themselves spies, they would be very difficult to stop. From time to time, the Chinese received large, and obviously illegal, amounts of information. But the most important aspect of this technique is that it is difficult to stop, and you don't even have many indictable spies to catch. Picking up small pieces of information from many sources is an ancient technique. The Chinese also make good use of the old Soviet "open source" opportunities. But combining this with the many minor bits of data gleaned from unsuspecting overseas Chinese scientists and engineers provided a constant supply of useful foreign secrets.
China and Russia were also quick to take advantage of espionage via the Internet. The West had more to steal and was more vulnerable, especially military and government organizations that could not afford to recruit the best Internet security talent to protect their networks. Corporations were another matter although it may be years before we discover just how vulnerable the defense firms actually were. In any event the Russians soon learned that having the tech was not as important as being able to build it, which they still could not do. Moreover the Russian economy never reformed like the Chinese did. When Russia got involved in places like Ukraine and Syria and used the best tech they had they discovered that not only was their new stuff exposed to Western scrutiny but that smaller, but Internet savvy nations like Ukraine and the Baltic States were able to scrutinize and weaken the Russian electronic weapons using a combination of some unclassified Western tech and their own local Internet talent. Syria was particularly embarrassing because the Russians found themselves watched carefully by an adversary, Israel, they had long known to be formidable. Allies like Iran, Syria and Turkey proved to be more liability than asset.
China found it could build a lot of the new military tech, because of several decades of economic (market economy) reform. But China was still hobbled by its lack of a Western style professional military and long traditions of military corruption.
The revelations of the Russian archives proved disturbing, and disruptive, in China as well. The Internet made it impossible to simply suppress all this. To their credit the Chinese leaders tried to use this to their advantage. For example in 2015 the Chinese government allowed some retired generals to publish articles pointing out that most of China’s past military defeats had been because of corrupt officers. All this has been recognized since the 1990s, but the problem persists and the Chinese rulers were admitting the obvious; that this ancient practice was still thriving in 21st century China. New laws had been passed to deal with it and some were energetically enforced, for a while at least, but the rot survived.
The biggest problem for many senior officials was not the corruption but the inability to keep it quiet. Thanks to the spread of cell phone and Internet use since the 1990s there were ample opportunities for Chinese, in or out of the military, to get more incidences of corruption recorded and exposed. Eventually most senior government officials realized that all their ambitious plans for regaining lost (over the last two centuries) territory meant little if the military was crippled by corruption. Now many more Chinese and foreigners were reconsidering actual Chinese military capabilities. This made it clear that the critics (Chinese and foreign) and historians (the Chinese believe in the lessons of history) were right and that the traditional corruption in the Chinese military was very much alive, very difficult to control and not likely to be eliminated without extraordinary efforts. The Soviets also recognized these historical facts and the role it was playing in weakening the communist hold on power. The archives showed how despite that awareness the Soviet empire died for lack of a solution to known problems.
Recent Chinese investigations, including many “speak freely without fear of prosecution” interviews with old soldiers discovered that the Chinese corruption didn’t even disappear, as many were led to believe, in the early years (late 1940s to 1960s) of communist rule in China. This was particularly demoralizing, as it was thought that there was some kind of “Mao Magic” in the 1950s when the leading founder of communist China, Mao seemed capable of doing anything. That included, it was later revealed, crippling the Chinese economy in a major way and causing a massive famine that killed over ten million Chinese. For the current corruption problem passing laws doesn’t seem to help much. For example in 2010 China enacted new laws that put additional pressure on the military to maintain quality standards in the construction and use of military equipment. At the time many were alarmed at why something like this was thought necessary. It's all because many Chinese assumed that if you got a government job, you had a license to steal. In the military, this meant weapons were built in substandard ways and equipment was not properly maintained. Military corruption is an ancient Chinese custom and accounts for most of the poor military performance in the past.
A more recent problem involves building a seagoing fleet, something China had never bothered with in the past. The details of how difficult this is are eagerly sought by many Chinese, captured with cell phone video and illegal Internet postings. The government still punishes some of these illegal journalists but has learned to make the most of it by using these truths to encourage Chinese who agree that a new Chinese empire is a good thing (and many Chinese do) to play their part and keep the heat on the corrupt naval commanders. This sort of peacetime reality check for officers is something new but it is making it possible for the Chinese to actually make some progress in training competent crews and maintaining warships far from China, something never done before. This sort of thing is essential if their new aircraft carrier force is to succeed and the government has to admit the obvious; that it will take decades to match Western levels of expertise.
Back in a non-communist Russia the new government tried various forms of democracy and by 1999 the country run by former KGB (secret police) officers who now admitted some of the past mistakes but have been unable to create anything that solves a lot of the old problems. The current Russian participation in the Syrian war and efforts to regain parts of the lost empire in the Caucasus and Ukraine are carried out by people who know of past errors but feel helpless to avoid repeating them. For example, by now many Russians know about how Russia got into a messy war in Afghanistan during the 1980s. At the time Russian military staffs proved they were quite good at calculating the “correlation of forces” for an operation and predicting the probability of success and that math did not look good when it comes to invading Ukraine. The Russians Stavka (general staff) famously warned against going into Afghanistan in 1979 on the grounds that the lack of roads and railroads there prevented Russia from putting enough troops (the “correlation of forces”) into Afghanistan to quickly crush opposition. Russian political leaders ignored this and less than a decade later withdrew from Afghanistan because the general staff had been right.
But there is one aspect of the new Cold War that is very déjà vu. That is the way American military commanders are responding to all the military theatrics by solemnly declaring that the enemy (Chinese, Russian, North Korean, Iranian) military threat may be more than the United States can handle. This sort of thing is reminiscent of the Cold War exaggerations of Soviet (Russian) military power. Even during the Cold War, many civilian analysts pointed out the tendency to overestimate the effectiveness of Soviet weapons, equipment, leadership and training. This distortion became pretty obvious after the Cold War, when much was revealed.
The puffery is back now with regard to China and Russia. It's no secret that China and Russia have long found it impossible to create effective military forces in peacetime. Not to underestimate them, but both nations have a long history of spectacular failure in this area. The Soviets proved that the historical lessons still apply and the Chinese make some serious efforts to deal with it openly.
But there were still a lot of military secrets and untried weapons (and troops) that make it an easy matter to report the other side's weapons as being, if only potentially, more lethal than they actually are. This culture of exaggeration, even during the Cold War, was often just called "professional courtesy." The Russian intelligence agencies also exaggerated the capabilities of American weapons. Thus the generals on both sides of the Iron Curtain had a better chance of getting more money out of their respective governments. Now it’s become clear that post-Cold War Russian and Chinese military capabilities are not as fearsome as Cold War era puffery would have it.
Despite that we have the Cold War attitudes returning and with that the return of professional courtesy when it comes to evaluating the state of the Chinese and Russian armed forces. North Korea and Iran suffer from the same form of self-deception. The goal of this self-serving spin (to get a larger defense budget and less criticism over corruption) appears to be the same as it always was and resistant to change.