Israel is worried about its next war with Iran. The last one was in 2006, and Iran used its Lebanese creation, Hezbollah, to fire thousands of rockets into northern Israel. While Hezbollah was defeated in that war, over a thousand Lebanese died, and many of them were not associated with Hezbollah. Thus many Lebanese who opposed Hezbollah, now saw the pro-Iranian organization as a heroic protector of Lebanon (even though Hezbollah started the war by kidnapping two Israeli soldiers.) Despite the presence of a UN peacekeeping force in south Lebanon, Hezbollah has been able to rebuild its network of bunkers, weapons storage sites and lookout posts. Israel recently gave the UN a map showing the location of 950 of these facilities. About 60 percent of these positions are bunkers, and another 11 percent are for storing rockets and other weapons. Most of these bunkers are in or near 270 villages, and many were constructed as part of repairs on homes and public buildings damaged during the 2006 war. But the UN will do nothing, as Hezbollah told the peacekeepers early on that if there was any interference, there would be a terror campaign against UN personnel. So the UN, and the peacekeepers stood aside as Hezbollah prepared for the continuation of the 2006 war.
Two years ago, Israel informed the US that Hezbollah now had several thousand larger rockets that could reach Israels largest cities (particularly Tel Aviv). Since it might take two months for Israeli ground forces to clear Hezbollah out of south Lebanon, Israeli cities would have to be deal with being hit with up to a hundred missiles a day. This convinced the U.S. to provide Israel with all the penetrating (anti-bunker) bombs it needed. But this still left Israel with the problem of how to deal with all those incoming rockets. Israel has an Iron Dome anti-missile system, but currently there are too few of these to prevent some rockets from getting through.
Thats not the only problem. Israeli Civil Defense authorities have concluded that they can only provide residents of Tel Aviv and Central Israel with 90 seconds warning, not the previous two minutes, of impending rocket attack. This is all because of the increased number of long range rockets possessed by Hamas (in Gaza) and Hezbollah (in southern Lebanon). Israel has a radar-based rocket detection system, and software that quickly calculates where an incoming rocket will land. At that point, the system automatically sounds the sirens in the target area, warning everyone to take cover, and wait for the all clear siren signal. Israeli intelligence believes that Hamas and Hezbollah, who are both clients of Iran (who also supplies the long range rockets) have so many rockets ready to launch, that the Israeli warning system would not be able to plot landing areas for all incoming rockets quickly enough. Thus the 25 percent reduction in warning time. However, starting two years from now, Israel plans to introduce a new anti-missile system (Magic Wand), which recently passed its first tests. But in the meantime, Israelis are advised to listen for the sirens.
For five years now, Israel has been constantly revising its civil defense plans, and how to deal with the growing arsenal of rockets and ballistic missiles aimed at it. Last year, for example, the military was ordered to disperse its stocks of supplies, equipment and spare parts to a larger number of (better protected) locations.
In addition to rockets fired by Hamas and Hezbollah, there is also concern that Syria would fire larger, and longer range, rockets armed with explosive or chemical warheads. Currently, the Israelis estimate that there would be as many as 3,300 Israeli casualties (including up to 200 dead) if Syria tried to use its long range missiles and explosive warheads against Israel. If the Syrians used chemical warheads, Israeli casualties could be as high as 16,000. Over 200,000 Israelis would be left homeless, and it's believed about a 100,000 would seek to leave the country.
Israel now assumes that Iran would fire some of its ballistic missiles as well, armed with conventional warheads. But the big danger is Syria, which is a client state of Iran. Syria has underground storage and launch facilities for its arsenal of over a thousand SCUD missiles. Armed with half ton high explosive and cluster bomb warheads, the missiles have ranges of 500-700 kilometers. Syria also has some 90 older Russian Frog-7 missiles (70 kilometer range, half ton warhead) and 210 more modern Russian SS-21 missiles (120 kilometer range, half ton warhead) operating with mobile launchers. There are also 60 mobile SCUD launchers. The Syrians have a large network of camouflaged launching sites for the mobile launchers. Iran and North Korea have helped Syria build underground SCUD manufacturing and maintenance facilities. The Syrian missiles are meant to hit Israeli airfields, missile launching sites and nuclear weapons sites, as well as population centers. Syria hopes to do enough damage with a missile strike to cripple Israeli combat capability.
Israel has long been aware of the Syrian capabilities and any war with Syria would probably result in some interesting attacks on the Syrian missile network. The SCUD is a liquid fuel missile and takes half an hour or more to fuel and ready for launch. So underground facilities are a major defensive measure against an alert and astute opponent like Israel.
But Syria has been adding a lot of solid fuel ballistic missiles to its inventory, and recently transferred over a hundred of these to Hezbollah, in Lebanon. Hezbollah and Syria are both clients (on the payroll) of Iran, and would likely coordinate an attack on Israel. Hamas, in Gaza, is a semi-client of Iran, and might be persuaded to join in as well.
Israel is developing new tactics to deal with the next Hezbollah war. The tactics are kept secret, as much as possible, to deny the enemy an opportunity to come up with countermeasures. The situation with Syria is a little different. No unclassified government planning documents have discussed what Israel would do in response to an attack using chemical weapons, but in the past, Israel has threatened to use nukes against anyone who fired chemical weapons at Israel (which does not have any chemical weapons). But current plans appear to try and keep it non-nuclear for as long as possible. For the Syrians, going to war with Israel is a very risky endeavor. Just using explosive warheads won't do enough damage to Israel to prevent Israeli troops from advancing on the capital of Syria. Chemical warheads on the missiles might stop, or slow down, the Israelis. Still a very long shot. But the Syrians do have the chemical warheads, although they may lack the nerve to ever use them.