The assassination of Benazir Bhutto has quickly changed the tone of the Iowa Presidential caucus campaign and the strategies of the various contenders. With only a few days left before the January 3 vote, any major international development would have impacted the U.S. candidates' plans and statements for a day or two, but the assassination of Bhutto seems likely dominate the news for several days, practically until the vote itself.

By now, nearly all the candidates have staked out positions or made statements designed to reinforce their key themes and messages. Clinton called for an international investigation, declaring that Pervez Musharraf had lost all credibility, and noting that she had met with Bhutto in the past. Obama was less specific and more cautious, Edwards also called for an international inquiry, but only after Hillary was first to broadcast this call on CNN. On the other hand, Edwards took the unusual step for a out-of-office candidate of calling Musharraf directly and reporting afterward that he had urged him to continue the democratization process. Richardson said the United States should call for Musharraf's resignation and withdraw all support for his government.

Republicans such as Giuliani, McCain and Thompson were less prone to prescribe actions beyond calling for vigilance. Giuliani was quick to draw a parallel to 9-11, but McCain said it meant that someone with his own kind of experience was needed in the White House.

As Erin notes, having a foreign affairs crisis front and center in the campaign — even as candidates such as Edwards say this should not be used as a political issue — may influence some of the Iowa undecided. So far, it seems that Hillary, Edwards, McCain and (maybe) Giuliani have the chance to gain points from their latest comments. The one who may lose traction is Mike Huckabee, whose Pakistan-related comments focused bizarrely on stopping Pakistanis from illegally crossing into the United States