As Pennsylvania went to the polls yesterday, Hillary Clinton sought to burnish her reputation as a hawk by warning Iran that as president she was prepared to "obliterate" the country, should it launch a nuclear attack against Israel.
"I want the Iranians to know that if I'm the president, we will attack Iran [if it attacks Israel]," Mrs Clinton said in an interview with the ABC network. She has been trying to sow doubts about the ability of her opponent, Barack Obama, a first-time Illinois senator, to lead the US in time of international tension while stressing her ability to handle "the toughest job in the world".
Her television ad featuring Osama bin Laden questions her opponent's ability to serve as commander-in-chief. "Harry Truman said it best: 'If you can't stand the heat, get out of the kitchen'. Who do you think has what it takes?" the voiceover says.
Yesterday's tough rhetoric on Iran is seen as part of that strategy, but Mr Obama rejected her remarks as sabre-rattling. "One of the things that we've seen over the past several years is a bunch of talk using words like 'obliterate'," the Illinois senator said. "It doesn't actually produce good results."
Mrs Clinton's remarks were an escalation of an earlier statement that she would offer a nuclear shield to Saudi Arabia, the Gulf states and Israel to protect them from Iran.
Yesterday she focused her words on protecting Israel: "Whatever stage of development they might be in their nuclear weapons programme in the next 10 years, during which they might foolishly consider launching an attack on Israel, we would be able to totally obliterate them. That's a terrible thing to say, but those people who run Iran need to understand that, because that perhaps will deter them from doing something that would be reckless, foolish and tragic."
Back in Pennsylvania, both sides were trying to play down expectations and win the perception game. Because of proportional representation, the delegate count is set to remain much the same even after yesterday's primary. The state is seen as a microcosm of the US, where a candidate's ability to win the swing constituency of white working-class voters is seen as key to success in the November presidential election against the Republican John McCain.
The Obama team says there is nothing Mrs Clinton can do now to change the underlying dynamic of the race in which her opponent has an insurmountable lead in the popular vote and the number of delegates. The Clinton campaign, which has seen a 20-point lead wither to single digits, was declaring that a win, however small, remains a win. "I don't think the margin matters," Mrs Clinton told NBC, while refusing to directly answer a question about what she would do if Pennsylvania did not hand her a crushing victory over her opponent. Her communications director, Howard Wolfson, told reporters: "I object to the notion that we need to achieve a certain standard of victory other than victory."
Demoralised and running out of money, the Clinton campaign hopes to translate a win into momentum and, even more crucially, money so she can stay in the race for the next round of primaries in North Carolina and Indiana next month.
Team Clinton has been cutting corners in recent weeks; using a smaller plane to get around and housing the travelling press pack in economy hotels. But Mr Obama continues to rake in money from millions of enthusiastic supporters in small $25, $50 and $100 contributions over the internet. Figures from the Federal Election Commission, show he had $42m in his war chest; Mrs Clinton has only $8m in the bank and debts of $10.3m.
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