Washington is doing one of the things it does best — speculating — as President Obama prepares to announce his Afghanistan withdrawal plan on Wednesday.

As aides say Obama is still finalizing his announcement, speculation ranged from a small withdrawal of only 5,000 or so troops right away to a gradual pullout of 30,000 or more troops by the end of 2012 (Obama’s re-election bid year).

The president “is reviewing the options and the assessments, and will have an announcement to make soon,” said White House spokesman Jay Carney.

A few things to keep in mind as Obama works on his speech set for Wednesday:

 There is going to be a withdrawal — it’s just a question of how many and at what pace.

 “In Afghanistan,” Obama told Democratic fundraisers last night, “we’re in the process of a transition where we are starting to give more and more responsibility to Afghans for their own security.”

Most of the discussion revolves around the number 30,000. That’s the number of additional troops Obama ordered deployed in his Afghanistan speech on Dec. 1, 2009.

 Obama is facing conflicting political pressures. The military wants to keep most of the surge troops there for as long as possible, while a rising number of congressional lawmakers want a larger pullout right away.

In a recent letter to Obama, 27 senators — including some Republicans — wrote that “given our successes, it is the right moment to initiate a sizable and sustained reduction in forces, with the goal of steadily redeploying all regular combat troops.”

“The costs of prolonging the war far outweigh the benefits,” the senators wrote.

— There will still be a lot of U.S. troops in Afghanistan even after this announcement. There are currently about 100,000 U.S. troops in the Afghanistan-Pakistan theater; if Obama pulled out all of the surge troops tomorrow there would still be about 70,000 there.

 — Another key date is 2014 — the year that the U.S. and its global allies plan to turn all security responsibility over to the Afghanistan government.

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