Israeli police detain a masked protestor during clashes in the northern Arab Israeli town of Umm el-Fahm, during a protest against the Israeli naval commando raid on a flotilla of ships carrying aid to Gaza

The Israel Defence Forces (IDF) is among the most feared, loathed and well-funded military in the world, with critics claiming it has committed thousands of war crimes over the years and has scant regard for human rights. Ordinary Israelis argue that it is necessary for the IDF to take extreme and often preemptive action – much like the boarding of the flotilla last week – because the country is targeted by terrorists on a daily basis. The IDF's mission statement, 'to protect the inhabitants of Israel and to combat all forms of terrorism which threaten daily life', clearly illustrates what Israel regards as its biggest enemy.

The IDF was founded following the birth of Israel in 1948 and has been in active combat on dozens of occasions over the years, such is Israel's unpopularity and controversial standing in the Middle East. The IDF is broken into four regional commands and has jurisdiction over the army, air force, navy, special forces and intelligence arms. Mossad, the infamous Israeli secret police force, works closely with the IDF, but is a separate organisation.

Military service is obligatory in Israel. Men must serve three years in the IDF when they reach 18 and women are conscripted for two years' service at the same age. All Israeli adults are members of the IDF Reserve until they reach 45 – they must complete one month of service each year and can be drafted at any time. There are 170,000 active soldiers in the IDF while the reserve numbers 450,000.

The IDF is an equal opportunities employer and allows women and gay people serve on the front line. Because young people must do military service, it is an opportunity for the IDF to single out the best and brightest, who are chosen to enter the Special Forces. Every branch of the IDF has Special Forces sections, which are euphemistically known as "reconnaissance units". Special Forces personnel are routinely trained in unarmed combat, the use of specialist weaponry and commando-type operations, similar to last week's assault on the aid boat.

Israel spends a staggering amount of money on defence each year. In 2008, the total budget was estimated to be in excess of $17bn (€14bn), which easily makes it the highest military spender in terms of GDP. This year's military budget will be the highest Israel has ever spent. The US gives around $1.8bn in military aid each year, mainly because of the hugely powerful Jewish lobby in the US.

Frightening array of weaponry

The array of weaponry at the disposal of the IDF is frightening. It has over 900 combat warplanes, including state-of-the-art F-15 and F-16 jet fighters. AH-64 Apache attack helicopters are among the 300-strong military helicopter fleet. It also has 13 warships, three submarines and 50 patrol boats. Two thousand tanks are also among the weaponry in the IDF's arsenal, as well as over 7,000 armored personnel carriers and other infantry vehicles.

Most of the IDFs equipment is imported but it also exports weapons. Ireland spent €14m on Israeli-made equipment in the past five years. There are also several surveillance aircraft which fly over Gaza taking satellite images which are used for security and to monitor terrorist activity.

Israel's powerful technology also allows it to eavesdrop into sites of strategic importance in Gaza. Israel is the only country that has its own operational anti-ballistic missile defence system and it is also capable of sending reconnaissance satellites into orbit. It is a badly kept secret that Israel has nuclear weapons at its disposal but its government refuses to confirm or deny this.

The IDF is legally allowed to assassinate terrorists, which it euphemistically calls "focused foilings". Such targeted killings have been approved by Israel's supreme court if the victims have participated in acts of terrorism and are planning future acts. Apache attack helicopters, F-16 fighter jets, specialist strike teams and snipers have all been used in the past to eliminate alleged terrorists.

The most famous instances of targeted killings occurred following the massacre at the 1972 Munich Olympics when 11 of Israel's Olympic party were murdered by Palestinian terrorists. Over the next decade, dozens of alleged conspirators were assassinated by the IDF and Mossad across Europe in a campaign of retaliation. This was later portrayed in the film Munich.

Another infamous assassination took place in 1996 when an expert Hamas bomb maker nicknamed 'The Engineer' was killed when he answered a mobile phone which contained explosives. The phone had been planted by IDF agents.

The IDF was also responsible for the controversial house-demolition policy in Gaza during the second intifada, which started in 2000, when bulldozers crossed the border and surrounded the houses of suspected terrorists before knocking them to the ground.

The aim of this policy was to encourage the families of would-be suicide bombers to discourage their loved ones from blowing themselves up because the families would be punished after they died.

Team of spin doctors

Israel is well-used to negative publicity around the world and always has a team of spin doctors ready to correct what it sees as inaccuracies. In an unusual move aimed at improving the IDF's image, a code of conduct was introduced in 2004 which stressed how IDF members should behave. Among the 11 rules are: "the use of force must be proportional"; "anyone who surrenders cannot be attacked"; and "soldiers must protect international aid workers, including their property and vehicles".