And so it begins:

“It’s certainly true that we in Congress will have input,” Sen. Charles E. Schumer , D-N.Y., said in a Jan. 9 conference call. But, he added, “The urgency of this economic crisis . . . is going to limit any haggling over competing approaches.” Schumer predicted that Congress would complete its work by a self-imposed Feb. 13 deadline and would enact a package greater than the $775 billion suggested by the Obama administration but still less than $1 trillion.

Nancy Pelosi wants tax increases. Barney Frank (and some other Democrats) want fewer tax cuts. Many Democrats want more infrastructure spending. And Charlie Schumer is already predicting that Democrats will do what comes naturally: spend more to try to accommodate everyone.

The signs are there that Congress is going to take Obama’s proposal and run with it, and send something to his desk that may not bear a great resemblance to what he suggested. This will be the moment that defines his economic legacy. Is he fully engaged to make sure that his crack team of experts and his whip man Rahm Emanuel knock some heads together to keep Congress in line?

Not exactly:

Obama acknowledged that lawmakers and administration officials will continue to “hone and refine” the proposal, even as they press for quick action. “There are going to be a whole host of good ideas out there, and we welcome all of them,” he said Jan. 9. “And we’re going to sift through all of them, and we are going to work in a collaborative fashion with Congress…”

Obama’s economic advisers, including former Treasury Secretary Lawrence H. Summers, met with Ways and Means Democrats on Jan. 9 to try to work through any disputes on the tax package. “He made a presentation, indicated some flexibility. We raised some questions, indicated some flexibility. And that’s kind of where it was,” said Richard E. Neal , D-Mass., a Ways and Means member. They will resume those discussions Tuesday afternoon…

Rangel added that he feels “a little uneasy” that lawmakers will have to make decisions so quickly on such a big bill that will need to satisfy senators, who usually insist on more deliberation. “We have broad latitude to negotiate,” he said. “Our problem is that time is not our friend, that this damn thing is moving so fast and they have so many different pieces to put together.”

This will be a serious problem for Obama, and he clearly doesn’t realize it. As things now stand, Congress is going to rewrite his tax cuts, increase the pork-barrel spending, perhaps add some tax increases, and inflate the overall price tag to nearly a trillion — or perhaps more. And Obama is giving them the green light, and he will have to sign it.