I've long been a proponent of military intervention against Iran, though not a ground forces invasion. As evidence builds that Iran is interfering in Iraq and is a major player behind terrorist groups like Hezbollah, we need to consider action. The newest development is that Iran isn't only behind Hezbollah, but they're training fighters for the terrorist group Hamas:

The Hamas commander, however, confirmed for the first time that the Iranian Revolutionary Guard has been training its men in Tehran for more than two years and is currently honing the skills of 150 fighters.

The details he gave suggested that, if anything, Shin Bet has underestimated the extent of Iran’s influence on Hamas’s increasingly sophisticated tactics and weaponry.

Speaking on the record but withholding his identity as a target of Israeli forces, the commander, who has a sparse moustache and oiled black hair, said Hamas had been sending fighters to Iran for training in both field tactics and weapons technology since Israeli troops pulled out of the Gaza strip of Palestinian territory in 2005. Others go to Syria for more basic training.

To analyze this, Iran has the power to launch a two-front war on Israel, as pointed out in that post. Add to that Iran's backing of Shi'ite militias in Iraq, and their backing of al-Qaeda in Iraq, and Iran now has the power to influence wars against both major powers for Democracy in the region, Israel and the United States. Military action needs to be on the table, because obviously the upper eschelon of Iranian leadership is behind this.