My take here. Joe Klein calls Obama's AIPAC speech both "strong" and "flawed":
[Obama] warned against the warmongering toward Iran that has overtaken some of the noisier precincts of the Jewish and evangelical communities. But then he bowed to the AIPAC crowd by saying that “containment” was not his policy with regard to the Iranian nuclear program. This directly contradicted his previous policy–which was that all options were on the table. Containment happens to be the option favored by most non-neocon foreign policy experts; it was a policy that proved a huge success against the Soviet Union, which threatened our national security far more profoundly than Iran does.
M.J. Rosenberg differs:
Both Netanyahu and his lobby wanted Obama to set out "red lines" that, if crossed by Iran, would lead to an American attack on that country. Obama offered no red lines. Yes, he said that the war option was on the table but, contrary to Israel's demands, made clear that it would come into play if, and only if, Iran develops a weapon, not when it develops a weapons "capability" as Israel (and its Congressional acolytes demand).
Walter Russell Mead believes Obama's tough talk is an attempt to keep the peace:
The dirty secret about President Obama’s generally successful effort to put more pressure on Iran through sanctions and diplomatic methods is that in the last resort its effectiveness depends on exactly the military threats that he would like to downplay. If the European countries weren’t terrified that Israel would act unilaterally, they would not have moved nearly as far or as fast as they have to isolate Iran. Isolating Iran, they hope, will calm Israel down enough so as to postpone or perhaps avoid the danger of war. If that threat disappeared, President Obama would not enjoy the kind of support for sanctions he has so far received.
The Dish 