The Bush administration's vision of 2003 – that an Iraq freed of Saddam Hussein would be a peaceful hive of democracy, the Germany of the Middle East, and a source of strategic strength for the US – long ago proved wildly optimistic. It's been replaced by the knowledge that Iraq is a frail state, a source of strategic weakness, and a likely drain on US resources for some time to come.
On one basic point, the US invasion of Iraq has been wholly successful: It toppled Saddam Hussein. That may not seem as important today as it did at one time, given that the invasion also did not find any of his vaunted weapons of mass destruction, and that the unintended consequences of his removal have proved to be numerous.
But many of Mr. Hussein's neighbors considered him a source of instability. At least one US ally in the region remains grateful he is gone.
"Any Iraq will be better than Iraq under Saddam, because the Iraq of Saddam had the ability to threaten Israel," says Shlomo Brom, a senior fellow at Tel Aviv University's Institute for National Security Studies and former head of the Israeli Defense Force's Strategic Planning Division.
Of the misjudgments made by the US prior to its initiation of hostilities, however, one of the most profound was its error in predicting how Iraqi society would react once freed of Hussein's grip. Pushed by extremists, it split into ethnic and sectarian groupings. It turned out that few Iraqis – or, at least, not enough of them – had been waiting for the day they could found a Jeffersonian democracy.
"The main lesson of the invasion of Iraq is that you cannot engineer society," says Mr. Brom.