Palestinian terrorist group Hamas has made substantial changes to its fighting forces in light of the beating they took during the 22 day war with Israel last January. As soon as the fighting ended (with the January 18th ceasefire), Hamas began an investigation into why they lost so badly. They concluded that their tactics of depending on roadside bombs and booby-trapped buildings didn't work. The Israelis knew about the bombs, and avoided them, and buildings rigged with explosives. The Israelis made heavy use of helicopters, UAVs and armored vehicles. In response, Hamas has now obtained anti-aircraft and anti-tank missiles from Iran, and is trying to smuggle in enough of these weapons in before the Israelis return.
Another change is training and discipline of their fighters. Although Hamas has nearly 10,000 armed men on the payroll, most of them are poorly trained. Last time around, the Hamas fighters were eventually ordered to get out of their security forces uniforms and fight in civilian clothes. This was done a few days after the Israelis entered the Gaza Strip, and Hamas realized that its fighters were no match for the Israeli troops. It was believed that having these men fight in civilian clothes would reduce Hamas casualties. If it did, it was not by much. But seeing all those Hamas security officials ditch their uniforms made Hamas look cowardly, and weak. Hamas had already lost the support of most Gazans by allowing the rocket attacks on Israel to continue through late 2008.
So, next time around, Hamas security forces are being trained to fight, and stay in uniform. The new infantry tactics depend on avoiding getting into battles with the Israelis. Instead, sniping and hit-and-run tactics will be used. All this is a long shot, since the Israelis have been very quick to adapt their tactics to whatever Hamas comes up with. But Iranian and Hezbollah advisors insist the new methods will work. This is largely based on the relative success of Hezbollah in their 2006 battle with the Israelis. Hezbollah actually lost that fight, being driven out of southern Lebanon by the Israelis. But Hezbollah declared it a victory, and that counts for a lot in Arab countries.
Until late 2008, Hamas thought they were invulnerable to Israeli attack. By placing so many of their military and government facilities in densely populated residential neighborhoods, they believed any Israeli bombing or shelling would cause high, and politically unacceptable, civilian losses. But the Israelis used surprise, more precision than expected, and innovations like calling civilians in the target area and telling them to get out before the bombs hit nearby. As a result, most of the 1,300 Palestinian dead were Hamas personnel, and nearly all the damaged structures were those used by Hamas.
The Palestinians cranked up the spin machine anyway, and accused the Israelis of war crimes and genocide. But Israel responded with a media campaign featuring aerial videos of Hamas fighters setting up mortars and rockets next to schools and residential neighborhoods. This didn't stop the usual alliance of leftists, anti-Semites and Islamic radicals from calling Israel names. But the mud didn't stick nearly as much as in the past. It's as if the Israeli campaign was seeking to humiliate and discredit Hamas, as much as it was to destroy military and government assets.
Hamas was satisfied with their propaganda campaign, but not with the performance of their combat leaders. Hamas found that most of their 10,000 armed men were useless because of poor leadership and training. Thus over 40 senior Hamas military leaders have been dismissed, and hundreds more lower ranking ones retrained, and reviewed (for their suitability to leading men in combat.) Hamas hopes to use anti-tank missiles (modern Russian models, preferably) from Iran, against Israeli armored vehicles (especially the tank size armored D9 bulldozers). Better communications systems are being developed, and better protection for the Hamas leadership.
Dozens of senior Hamas officials were killed by smart bomb attacks. The families of these Hamas leaders often died as well. Israel ignored Hamas attempts to protect its leaders by surrounding them with women and children in residential areas. What dismayed Hamas the most was Israel finding the location of their officials. Even before the ceasefire took effect on the 18th, Hamas death squads were rounding up the usual suspected (members of rival Fatah, and anyone else unlucky enough to be suspect) for torture, mutilation or execution. The UN did not pay much attention to this, as it has been going on for over two years in Gaza. In that time, over 400 Fatah members have been killed by Hamas death squads, and many more Fatah (and any other Hamas rivals) tortured, wounded or jailed. Hamas apparently didn't realize that there were other ways to get target locations, besides informants on the ground. But all they understood was informants, so Hamas went after informants, and Hamas felt better after. But the bombings continued.
Israel destroyed most of the smuggling tunnels that bring weapons (particularly long range rockets for attacks on Israeli civilians) into Gaza. Israel wants Israeli or American sensors and technicians prowling the Egyptian border to detect all the tunnels, and for Egyptian border guards to destroy them. Hamas opposes this (as do many Egyptian officials, especially the ones who benefit from the bribes of the tunnel operators). Negotiations continue, as does the smuggling.
Ultimately, Hamas found that hiding their senior leadership in hospitals or orphanages offered the best protection from Israeli attack. Weapons and key items of military equipment could also be stored there. Hamas apparently exercised some restraint, in to what degree they took over these institutions for military purposes. Someone in Hamas began doing the math, and realized that, at a certain point, a hospital full of weapons and Hamas personnel stopped being a hospital to Israeli commanders, and became a prime target. This tactic will continue.