Troop withdrawal from Iraq?

I'm curious to hear what our military experts (Arthur, Dave) think about withdrawing troops from Iraq. Recently, an editorial was written on that very idea and now there's reports in the British press that the US and UK are planning to withdraw troops by early 2007.

The crux of the argument now is that:

• First, Iraqi politicians will not apply sustained pressure to their security forces to improve themselves so long as they know that the Americans will remain to protect the state from the insurgents.
• Second, the Iraqi units themselves will not grow in capability and confidence so long as they are relying upon American command and control, firepower, and tactical acumen.
• Third, the political leaders of Iraq’s three main factions will not make difficult compromises so long as the United States remains in Iraq.
• Fourth, the American presence fuels all four social sources of insurgent support.

Read the editorial for details. So guys... do you agree?