Hamas' Armed Wing Numbers In The Tens Of Thousands, And It's Ready For A Long Conflict

As the conflict in Gaza progresses, Hamas has shown an astounding ability to continue its attacks in the midst of Israel's ongoing offensive.

Israel's Operation Protective Edge is close to entering its fourth week - but Hamas has managed to continue to launch rockets while carrying out strikes within Israel.

Hamas' resilience is owed partly to the group's stockpiling of rockets, along with its ability to manufacture its own weaponry. And Hamas' extensive tunnel system has allowed the group to continue carrying out attacks, such as a strike against an Israeli watchtower on Monday that killed five soldiers.

But there's another source of Hamas's durability: It has an enormous number of available fighters.

Because of Hamas' status as a nonstate militant group, there is no definitive count of the number of fighters the organization actually has. It is possible that, because of the group's sometimes loose cell-based structure, not even Hamas leaders have an exact idea of the number of militants they command.

However, most estimates of the manpower of Hamas' military wing, the Izz al-Din al-Qassam Brigades, lists the force's manpower in the tens of thousands with somewhere between 10,000 and 20,000 soldiers. In 2009, the International Crisis Group estimated that the Qassam Brigades had 7,000 to 10,000 full-time members with a reserve of 20,000 soldiers.

IHS Jane's listed the group as having 13,000 well-trained and well-equipped personnel in September 2013. A senior Palestinian military intelligence official also told Jane's that the Qassam Brigades had upwards of 100 MANPADS (man-portable air-defense systems) that had been looted from Libyan arsenals after the fall of dictator Muammar Gaddafi - although these would have limited effectiveness against Israel's air force due to countermeasure systems the Israelis had put in place.

The Qassam Brigades have admitted that they have used the time since the last war with Israel to better prepare for a long confrontation with a powerful conventional army. These preparations have included setting predetermined times for rocket launchers, along with deploying decoy launchers to fool the Israelis.

Still, Hamas isn't the largest or best-equipped militant group in the Levant. Hezbollah, for instance, is thought to be creating a "popular army" throughout the wider Lebanese and Syrian region that could number between 50,000 and 150,000. Hezbollah, like Hamas, does not publish official numbers regarding its military strength.

Since the start of the operation in Gaza, more than 1,200 people have died in Gaza. The U.N. estimates 70% to 80% of the dead are civilians.