A new poll conducted by the Pew Global Attitudes Project finds that 63 percent of respondents in the U.S. “would turn to military force to prevent Iran from going nuclear.” But the pollsters questions contain unproven assumptions about the effectiveness of military strikes and suggest that failure to act militarily may hasten an Iranian nuclear weapon.

Respondents were asked to choose [PDF, page 27] between “preventing Iran from developing nuclear weapons, even if it means taking military action,” or “avoiding a military conflict with Iran, even if means Iran may develop nuclear weapons.” Built into these questions is the assumption that military action can prevent Iran from acquiring nuclear weapons or, conversely, that the lack of military action may ensure an Iranian nuclear weapon. Policy experts in Israel and the U.S. have consistently challenged this understanding of the Iranian nuclear showdown.

Last month, former Israeli internal security chief Yuval Diskin warned that :

[Israel's leadership] presents a false view to the public on the Iranian bomb, as though acting against Iran would prevent a nuclear bomb. But attacking Iran will encourage them to develop a bomb all the faster.

Indeed, the pollsters at Pew could take some lessons from Diskin about avoiding false trade-offs between bombing Iran and preventing an Iranian nuclear weapon. They could also have listened to Israeli Deputy Prime Minister Dan Meridor who observed that “an attack on Iran wouldn’t add anything to our security.” Or they could have watched former Israeli spy chief Meir Dagan’s warnings on 60 Minutes that an attack on Iran would “ignite regional war” and “there’s no military attack that can halt the Iranian nuclear project. It could only delay it.”

In the U.S., Secretary of State Hillary Clinton emphasized that “giving diplomacy a chance” is the best “way forward,” and former U.S. Ambassador to the U.N. (appointed by George H.W. Bush) Thomas Pickering warned that “[A military strike] has a very high propensity, in my view, of driving Iran in the direction of openly declaring and deciding [...] to make a nuclear weapon.”

Finally, and from perhaps the least political source, the Congressional Research Service (CRS) found that “an attack could have considerable regional and global security, political, and economic repercussions” but “it is unclear what the ultimate effect of a strike would be on the likelihood of Iran acquiring nuclear weapons.”

This uncertainty was nowhere to be found in Pew’s questions which posed a clear tradeoff between taking military action to destroy Iran’s nuclear program and “avoiding a military conflict” at the expense of Iran acquiring a nuclear weapon. This tradeoff presented to poll respondents fails to take into account the overwhelming evidence that no such trade-off exists. President Obama has committed to “preventing Iran from obtaining a nuclear weapon” and said it was “unacceptable for Iran to have a nuclear weapon.” But the willingness of politicians and pollsters to portray a tradeoff between military action and Iran’s acquisition of a nuclear weapon promotes an inaccurate set of policy choices which, ultimately, may undermine efforts to resolve the Iranian nuclear crisis.

Public support for keeping U.S. forces in Afghanistan has fallen to a new low. A new poll from the Pew Research Center finds among the all important swing voters, over half, 59 percent, favor withdrawing from Afghanistan as soon as possible. Swing voters make up 23 percent of registered voters.

The numbers in favor of a withdrawal draw even higher among voters who say they will support President Obama’s re-election. Sixty-five percent of Obama supporters say they would favor a quick withdrawal from Afghanistan and Republican voters are also leaning towards removing U.S. troops with 48 percent of Mitt Romney supporters favoring a troop pullout as soon as possible. Only 46 percent of Romney supporters and 28 percentof Obama supporters reported they would favor keeping U.S. forces in Afghanistan until the security situation stabilizes.

Results from the April Pew poll reflected a record-low support for keeping U.S. troops in Afghanistan as the U.S. public tires of the decade long war and recent Taliban attacks and U.S. atrocities against Afghan civilians. A new incident made headlines this week when photographs of U.S. soldiers posing with bodies of dead insurgents were published by the Los Angeles Times.

Overall, public opinion on the war has turned more negative in the past month. Since March, the percentage of poll respondents describing the U.S. military’s efforts in Afghanistan as going “very/fairly well” has dropped from 51 percent to 38 percent.

The U.S. public’s war weariness appears to be having an impact on the presidential campaigns where Mitt Romney, who had previously criticized Obama’s war policy as “misguided and naïve” for announcing plans to hand over primary combat responsibility to Afghan forces next year, has accepted, in large part, the White House’s troop drawdown strategy.

Romney now says that he wants to bring troops home as soon as possible but only when “our general think it’s O.K.” or “as soon as that mission in complete.” In an email to the New York Times, a Romney aide acknowledged that despite the campaign’s frequent criticisms of the White House’s 2014 target for a complete U.S. withdrawal, “Pending full review of conditions on the ground, Governor Romney would abide by the 2014 target for transitioning combat operations recommended by the military commanders.”