Updated May 11, 2012
The Growing Threat
Hamas and Gaza's militant groups continuously work to improve their rocket capabilitiesâ€”such as range, accuracy, and shelf lifeâ€”either through developing new technology or by smuggling-in improved weapons from abroad. According to one member of the al-Aqsa Martyrs Brigades interviewed in the first half of 2011, Grad rockets, once difficult to acquire, have been coming through the tunnels at an increasing pace so that now all militant groups have them.
Israel, for its part, continues to work against the tide, locating and preventing vessels with weapons for Gaza from reaching their destination. In March 2009, an Iranian weapons convoy in Sudan believed to be carrying Fajr missiles intended for Hamas was destroyed, likely by Israel. The Iranian Fajr missile is capable of hitting Tel Aviv. And in March 2011, the Israeli Navy boarded and searched an Egypt-bound ship called "Victoria" after confirming reports that the vessel was carrying illicit arms. Israeli officials determined that the weapons, including anti-ship missiles, were sent by Iran and were on their way to the Gaza Strip.
In August 2011, Brigadier General Yaron Levi, the Navy's intelligence chief, reported that Hezbollah's model "is being copied today to the Gaza Strip. In the future, we will have to deal with missiles, torpedoes, mines, above-surface weapons and underwater ones, both in Gaza and Lebanon." He added, "we assume that everything that Iran has can be brought to theaters closer to us."
The process of arming Gaza has only been made easier by the Arab uprisings of 2011. Of most importance are the changes taking place in Egypt; the interim government that took over after Hosni Mubarak's fall dismantled many of the former ruler's restrictions on Gaza meant to prevent Hamas from increasing its weapons capabilities. For example, after Mubarak's leave, Egypt stopped construction on the steel wall that was to prevent smuggling between Egypt and Gaza, decreased its level of security in the Sinai Peninsula as a result of the chaos, and opened its border with Gaza to pedestrian traffic in May, allowing rocket or military experts interested in training Hamas easy access. According to Israeli defense officials, in the months following Mubarak's fall, the decrease in security allowed Hamas to acquire improved high-trajectory rockets, ready-made explosive devices, anti-tank missiles, and possibly anti-aircraft missiles. That same report cites that the war in Libya also opened new avenues for smuggling weapons to Gaza.
Indeed, since Libyan dictator Muammar Qaddafi's fall, it is believed that Grad missiles with ranges of 60-70 miles, shorter range rockets, guns, and ammunition have been smuggled into Gaza from Libya. There is also the fear that MANPADS (Man-Portable Air Defense Systems), which are capable of shooting down an aircraft flying up to 12,000 feet, have found their way to militants on Israel's border. In September 2011, it became clear that thousands of advanced weapons, including deadly heat-seeking surface-to-air missiles, went missing during Libya's uprising. Soon thereafter, Egypt acknowledged that over the previous few months it arrested five groups of smugglers on their way to Israel carrying weapons from Libya, including anti-aircraft missile launchers.
Gaza's militant groups also continuously develop new techniques and tactics to use in their fight against Israel. According to a July 2011 report, the militants in Gaza now use Google Earth, a satellite mapping tool developed with the help of the CIA, to pinpoint the exact location of target sites in Israel, such as specific roads or buildings, to aim their rockets.
Hamas uses an intricate network of underground tunnels to bring goods and people in-and-out of Gaza to escape Israel's blockade of the Strip. Goods that come through the tunnels include: fish, sheep, infant formula, and other food products; clothing and shoes; construction materials such as cement; fuel; cigarettes; electrical appliances; toys; drugs; medicine; and vehicles such as motorcycles and fully assembled cars. Of utmost concern for Israel, however, is Hamas's smuggling-out of people for advanced training, as well as its smuggling-in of experts, rocket parts, and other weaponry.
The tunnels are impressive structures; they can run over 400 feet long, lie more than 40 feet deep, and have ventilation shafts and phone lines. It takes months, and tens of thousands of dollars, to build one. Homeowners who allow Hamas to use their houses to conceal tunnels can receive upwards of $20,000 in compensation funds for their assistance. Over 1,000 tunnels are believed to cross underneath the Egypt-Gaza border.
On August 18, 2011, Gaza militants carried out a coordinated terrorist attack in southern Israel that killed eight Israelis. The terrorists are believed to have used the tunnels between Gaza and Egypt to travel to the Sinai, and then cross the porous Sinai-Israel border further south into Israel. As a result, Israel moved-up the completion date for a fence it is building along the border with the Sinai Peninsula to prevent infiltration and similar attacks.
While most reports on Hamas's tunnel system usually point to smuggling only, the group also uses a large tunnel infrastructure inside Gaza to move items and people, such as top leaders, around the small piece of land without Israeli detection. The tunnels also allow Hamas militants "to attack and retreat, to ambush and kidnap," and to blow up Israeli vehicles driving over the tunnels without them suspecting anything. In 2009, Hamas used the cease-fire with Israel to build underground rocket systems that could be detonated remotely and are connected to the tunnel infrastructure so that Hamas fighters can access the rockets as needed without detection.
Hamas's smuggling activities and tunnel building can only be expected to continue unabated at this point. While Israel occasionally destroys a tunnel or two with an aerial bombing in response to a rocket launch, Egypt is the only country truly capable of preventing Hamas's smuggling and tunnel efforts. But since Mubarak's fall in February 2011, it is unlikely that Cairo will strictly enforce security measures on the Gaza-Egypt border. An August 2011 report by the AFP confirmed that tunnel activity spiked after February.
Other forms of attacks
Aside from rocket attacks, Gaza's militants terrorize Israel's population in other ways such as with shootings or planting improvised explosive devices (IEDs) near the border powerful enough to harm IDF troops policing the area. Between 2000 and 2009, Palestinians in Gaza carried out over 5,000 shooting attacks against Israelis. And while a majority of the attacks occurred before Israel withdrew from the territory in 2005, there were 77 incidents in 2006, 98 in 2007, and 82 in 2008 before the number dropped to just 4 in 2009. Most of the attacks are shootings at farmers working their fields.
Hamas and other militant groups in the Gaza Strip also routinely fire mortar shells into Israel. Mortars are high-trajectory weapons that have a shorter range than the rockets launched from Gaza, but are still deadly. Between 2001 and 2010, militants in Gaza fired more than 4,300 mortar shells at Israeli soldiers and civilians.
 "The Challenge of Gaza," The Saban Center at Brookings, Analysis Paper 23 (2011): 5.
 "The Challenge of Gaza," 7.
 Ibid., 16-17.
 Ibid., 6.