The more one considers the replacement of Donald Rumsfeld by Robert Gates as the US Secretary of Defence, the more it looks like a major shift in the Bush administration's foreign and security policy. Mr Gates is a realist not a neoconservative.
He is an open supporter of engaging Iran and Syria in pursuit of stability in Iraq and a peace settlement between Israel and the Palestinians. The "axis of evil" concept which has excluded Iran and Syria from US direct diplomatic negotiation is incompatible with such an approach.
Mr Gates is also a prominent member of the cross-party Iraq Study Group led by James Baker and Lee Hamilton. Their forthcoming report is widely expected to recommend a gradual military disengagement from Iraq and comprehensive talks with its neighbours to contain regional violence as that withdrawal takes place. His management style stresses delegation to expertise and experience, the very opposite of Mr Rumsfeld's aggressive micromanagement which so alienated the military top brass.
After the Democrats' congressional victory the stage is set for a decisive shift in US foreign policy, putting greater emphasis on multilateralism and diplomacy. This must start with Iraq, which has reached crisis point. It will be difficult indeed to retrieve the credibility the US has lost as a result of the invasion and subsequent mismanagement of the occupation in Iraq.
But a sea change of policy, if it does indeed transpire, will generate goodwill in Europe and more gradually in the Middle East. US power is such that a change of course must be responded to throughout that region.
This will pose dilemmas for those who had written off the Bush administration; and it may be too late simply to go into reverse. The world has changed over the last six years. In the security sphere, Europeans have taken on new responsibilities in the Balkans, Lebanon and Afghanistan. They will be reluctant to shift ground back to a US-dominated Nato, if that is demanded by Washington. In the same way, the Iranian and Syrian leaderships, and conservative regimes in Jordan, Syria and Egypt, will seek to extract a price for co-operation. So will the Israelis and Palestinians. But that will open up opportunities for political progress too.
Mr Rumsfeld's departure is the key element of this shift in US policy. He was the link to Vice-President Cheney, the administration's ultimate hard man, who has frustrated Condoleezza Rice's efforts to broaden the scope of US diplomacy. After the events of this week, Mr Cheney looks very isolated.
