Yesterday’s briefing by the CIA to Congress on a purported attempt by Syria to get nuclear weapons with North Korean help drives home the foreign problems facing the next occupant of the White House, and the three contenders in their campaigns to get there.

The next president’s in-tray “will be filled with more trouble than any newcomer has faced”, argues Strobe Talbott, former Deputy Secretary of State for President Clinton and head of a Washington think-tank, the Brookings Institution.

The problems threaten to make any president, or any candidate, look bad. The complexity of the threats, the high stakes and the huge expectations riding on George W. Bush’s successor (at the very least, to be different from him) have circumscribed what John McCain, Hillary Clinton and Barack Obama have said on the campaign trail, forcing the Republican candidate and the two remaining Democratic contenders into taking positions that may be untenable.

When Bush became President in January 2001, the United States had a booming economy, budget surpluses and no known enemies of any significance, says Philip Gordon, also of the Brookings Institution, one of a team advising Obama on foreign policy. Now, all those factors are reversed.

No surprise that Iraq, where the United States still has more than 140,000 troops, has dominated the election campaign so far, and will be the first huge decision confronting the new president.

“It is the elephant in the room”, one Democratic strategist said. “As this President [BUSH]has made clear that he is not going to make any significant decision [on what to do with them], the new president will have to.”

After that, in the in-tray, comes Afghanistan, while Iran may well take itself to the brink of having a nuclear weapon in the new president’s first year, Gordon says (his own view, he adds, not the Obama campaign’s).

More widely, there is militant Islam, Pakistan, and the difficulty of striking the right tone on those threats when so many Americans are fed up with war and the War on Terror, and are alarmed instead by the slowing economy. China is growing stronger; Russia is a significant force only in its dreams, but its aggression is growing as its power shrinks. North Korea wants lethal weapons; the Middle East probably wants them too, and then there are the giant global problems of climate change, disease and poverty.

Iraq has already given McCain, Obama and Clinton most trouble in framing policy, to the point where each, in office, might find it hard to stand by campaign promises, even though they are hedged around with qualifications.

McCain, famously, has vowed to keep an American presence in Iraq for “a hundred years” if necessary. Obama has been at the other extreme, voting against the war in the Senate, and promising a rapid drawdown of troops after taking office, while leaving some undefined American presence in the country. Clinton, who voted for the war, has since claimed that she considers herself misled by the intelligence presented to Congress. She has also committed herself to bringing back troops, starting within 60 days of taking office, “subject to consultation with commanders” (which offers some wiggle room).

Talbott argues, surely rightly, that a “situation on the ground which is probably very messy [when the next president takes over] and which would be undermined by a precipitate pullout” could make it difficult for any of the politicians to stick to these campaign positions.

Similarly on Iran, the three candidates span the range of options, with McCain sounding toughest, arguing that the only thing worse than military action against Iran would be a nuclear-armed Iran. Randy Scheunemann, his director of foreign policy, points out, however, that McCain believes that sanctions and other pressure have a long way to go and that “we are not anywhere near being faced with that decision.”

Clinton talked this week of bombing Iran if it attacked Israel. Meanwhile, Obama, in a position mocked by the other two, which he has since been qualifying, suggested talking to the Iranian President, Mahmoud Ahmedinejad, without preconditions.

Will Marshall, head of the Progressive Policy Institute, a Democratic think-tank, argues that even though Clinton has sometimes sounded almost as tough as McCain on security, there are still real ideological differences between Republicans and Democrats over the role of the United States in the world. “John McCain grew up in the Cold War,” he points out, and Marshall believes that the Republican candidate is more convinced of America’s duty and moral authority to act to solve foreign conflicts, using force if necessary.

Where each of the three is similar (and carefully different from Bush) is in a professed commitment to work with allies. But it is hard to work out what this conciliatory tone will mean in practice. In addition, as many analysts are keen to point out to European governments waiting eagerly for a less high-handed Administration, all three contenders, in office, would make demands, such as more troops in Afghanistan, which European allies would find uncomfortable.

The trouble which the three contenders have had in framing foreign policy shows the difficulties ahead for the next president. None of these problems will flatter the next occupant of the White House. Any could make him, or her, look reactive, or overwhelmed. Expectations are bound to be disappointed, within the United States and abroad.

All the same, the next president has an extraordinary opportunity. He or she starts with a clear brief on what Americans do not want: the sacrifice of 4,000 military lives and billions of dollars on a cause which strengthens enemies and leaves allies bemused.

If the new president survives the torrent of issues raining down, then it is a chance to set a very different tone for America’s role in the world, one which could last for decades.

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