Hamas, the Palestinian terror group that runs Gaza, is being terrorized by other Islamic terror groups that have been given sanctuary in Gaza. Islamic terrorists are supposed to help each other, or so goes the popular perception. The reality is quite different. Islamic terrorist groups are often at war with each other. Each is on a Mission From God, and for religious conservatives, God does not send mixed messages, at least according to these guys, so strife between Islamic terrorist organizations is kind of inevitable. Despite the long list of examples, Hamas thought it could tolerate smaller Islamic radical outfits in Gaza. The idea was to use these other groups as allies against their common enemy; Israel. Sometimes this worked, but never for long. For example, the smaller outfit (Jaysh al Islam) that helped Hamas kidnap an Israeli soldier (Gilad Shalit) five years ago, was destroyed by Hamas (over twenty dead and over a hundred wounded) three years after Shalit was grabbed. Hamas thought this bit of tough love would persuade similar groups to behave. Didn't work, and it now finds these tiny rivals recruiting many of the most enthusiastic Hamas terrorists.
All of this is a growing problem in Gaza, for all the Palestinians there and neighboring nations as well. Yet Hamas still lets Islamic terrorists move in. Hamas has made Gaza a sanctuary for Islamic radicals, a process that it has been unable to reverse. That's because the other sanctuary areas are, well, worse. Somalia is in chaos, and Pakistan's tribal territories are under heavy pressure from the Pakistani Army and CIA UAVs armed with missiles and too much information about everyone's location. Thus while Gaza is small, and under constant threat of Israeli attack, it is relatively safe. And the tunnels into Egypt give these terrorists access to the rest of the world, via an underground network of criminals and Egyptian Islamic radicals who will, for a price, help you get out of the country, or get weapons, equipment and false ID. The recent change of government in Egypt has not changed this, and is unlikely to do so anytime soon.
The Egyptian government does not cooperate with this arrangement, as many of the Islamic radicals in Gaza consider the Egyptian government an implacable enemy. That's certainly true, as Egypt destroyed the radical wing of the Moslem Brotherhood in the 1990s (some of the survivors joined al Qaeda in Afghanistan). But Egypt is full of corrupt officers and officials. As long as Hamas can come up with bribes, the Egyptian bureaucracy will come up with someone to take the money and look the other way.
Hamas does not want to run a sanctuary for terrorists, but as an Islamic radical organization, it does not want to get into wars with other Islamic terror groups. This is all too easy a trap to fall into. In most areas where Islamic terrorists are active, factions among the terrorists are fighting each other. This does not get a lot of media play, but it gets a lot of Islamic terrorists killed. Think of it as a dirty little secret in the terrorist world. Hamas would rather not join this club, at least not in a big way. But by controlling Gaza, and positioning yourself as big-time Islamic radicals, you must pretend to support your smaller rivals, until their ungrateful behavior forces you to kill them. Quietly. If possible.
Hamas has not been able to avoid terrorist-on-terrorist bloodshed. The most recent cause for retaliation is the smaller group accusing Hamas of not being radical enough. That's been easy to do, largely because of the two year old ceasefire with Israel. This was accepted to keep Israel from retaking control of Gaza and exterminating Hamas. The ceasefire also gave Hamas time to build up its arsenal (especially with long range Iranian rockets), along with the defenses in Gaza (bunkers, booby traps). Hamas has a vague plan to make a large scale attack on Israel, and feels its chances would be much enhanced if they could only stockpile enough weapons. Thus Hamas feels compelled to pressure, even kill, other terrorists who do not go along with the ceasefire. So far, Hamas has been able to avoid large scale bloodshed with fellow terrorists. But this is not expected to last. The Hamas crackdowns on smaller terror groups is increasing. Hamas blames its rival Fatah for arming and encouraging some of these troublesome terror groups. But groups like that have no problems finding arms, or encouragement to fight. Hamas will have a hard time clearing the Islamic radical competition out of Gaza. Worse yet, many Hamas members do not like fighting other radicals, and are increasingly switching sides.