Q&A: Face-to-face in Gaza: tactics of Israel and Hamas

Jan 12 (Reuters) - Israel kept up its offensive against Hamas in the Gaza Strip for a 17th day on Monday. Following is an overview of the tactics and weapons deployed by each side.

Q - What are the strategies?

A - Israel's aim is to stop rocket fire from Gaza on its southern towns and to do so it has set about pummelling Hamas from the air and the ground to a point where the Islamist movement is either unwilling or unable to seek another confrontation with the Jewish state. It has not, however, made a commitment to breaking Hamas's control of the coastal enclave.

Israel is also intent on ensuring Hamas cannot rearm again, and to that end it wants to destroy smuggling tunnels between southern Gaza and Egypt and stop them from being rebuilt. To do so, it is considering seizing the land along the border, known as the Philadelphi corridor, a potentially risky escalation.

Hamas, whose ultimate goal is an Islamic state in all of what was Palestine in 1948, appears intent on firing as many rockets as it can each day as a show of defiance and as a signal that it remains unbowed. It may well hope to claim victory just by living to fight another day.

The length of Israel's offensive faces pressures from international diplomacy and an Israeli election on Feb. 10 -- heavy losses among troops would not be popular with voters.

Q - What is the balance of arms?

A - Israel has among the world's most technologically advanced militaries, with more than 150,000 active personnel. Several thousand well-trained regular troops and reservists are already inside Gaza or on standby. They benefit from high-tech surveillance and communications equipment and can call on massive firepower from tanks, aircraft and navy gunboats.

Hamas has an estimated 25,000 fighters with small arms and rocket-propelled grenades. Israel says it also has more advanced anti-tank missiles and may have shoulder-fired anti-aircraft missiles capable of hitting helicopters or low-flying planes -- though it is not clear such weapons have been used. Palestinian gunmen say they have prepared a matrix of deadly ground obstacles, from minefields to trenches and booby traps.

Hamas has carried out dozens of suicide bombings in Israel and says its men -- and women -- could resume the tactic now.

Q - What are Israel's tactical advantages?

A - Though Israel's troops withdrew from Gaza in 2005 after 38 years of occupation, its intelligence services have studied the territory extensively, anticipating a showdown with Hamas.

Wary of repeating the setbacks in their 2006 war against Lebanon's Hezbollah guerrillas, in which 157 Israelis died, the army has trained extensively and improved communications. Popular anger among Israelis at some 8,000 rockets and mortars fired into Israel from Gaza, killing 18 people from 2000 until the offensive began, has helped motivate the troops.

Israeli commanders have imposed new levels of censorship and information security to prevent leaks from the battlefield which might tip off the Palestinians as to military deployments.

The relatively slow progress of Israel's armed forces in Gaza so far, and their relatively low casualty rate, suggests they are advancing slowly and carefully to avoid being ambushed.

Q - What are Hamas's tactical advantages?

A - Nothing beats a defender's first-hand familiarity with the terrain. Hamas can also rely on support from many civilians.

The group appears to be trying to draw Israeli forces into heavily populated areas, where warrens of alleyways would make their tanks and some of their air support irrelevant. While Israeli forces are edging in on the city of Gaza from the north and south, they have avoided going deep into its streets.

Hamas leaders have described the current Gaza combat as a fight to the finish, so the guerrillas' motivation -- stoked by religious zeal -- is high. The ethos of self-sacrifice can make Islamist fighters hard for conventional forces to counter.

The Palestinians also appear set on capturing Israeli troops to add to Gilad Shalit, a soldier seized from across the border in 2006. Success in this, and any Hamas threat to kill captives, could allow the Palestinians to stave off Israel.

Q - What are Israel's tactical disadvantages?

A - Excessive Israeli caution in pushing into Gaza could become a liability if it turns troops into static targets.

Aware of pressure from its diplomatic allies, Israel says its forces are exercising all possible effort to avoid causing non-combatant casualties, though it appears many of the 900 Palestinian dead counted by Gaza medics have been civilians.

Any especially heavy loss of civilian dead in one incident, or troop losses, could demoralise soldiers by setting off investigations and recriminations along the chain of command.

Israel has tried to deflect criticism of civilian casualties by blaming Hamas for deliberately operating from built-up areas. After medics said 42 people were killed last week when mortars hit a school, the army said it was returning fire at militants.

Q - What are Hamas's tactical disadvantages?

A - While it won the 2006 parliamentary election and routed the Gaza forces of the rival Fatah faction the following year, Hamas does not enjoy unanimous popular backing. The impact of 17 days of war may have damaged Hamas's standing, and the group's tactic of firing rockets is far from universally popular. At the same time, holding out against Israel may bolster its image.

Hamas has depended heavily on smuggling through Egyptian border tunnels for both arms, funded by Iranian and Syrian allies, and for supplies for Gaza's population. Israel has struck hard at those routes, threatening Hamas's arsenal and also its ability to satisfy local consumers. (Writing by Dan Williams; additional reporting by Nidal al-Mughrabi and Luke Baker; editing by Alastair Macdonald)