As predicted, Republicans in the House have grudgingly allowed a two-month extension on the payroll tax holiday, on the condition that they can impose a deadline on Keystone XL pipeline approval. President Obama had postponed approval for a year, based on evidence that the environmental analysis was flawed, but Republicans want a decision NOW NOW NOW or they're taking their ball and going home. Or anyway they're taking middle-class workers' tax money and unemployment benefits and going home. So now Obama has 60 days to rule on the pipeline before the whole shitty process starts over.

Grist has dug into the weird psychology and possible implications of this move a couple of times, before the tantrum was official policy. Scott Rosenberg thinks it's a dick-sizing contest:

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To understand why the pipeline has become the GOP's line in the tar sand, you have to fathom the nasty logic of alpha-male political messaging in the age of Fox News. You have to grasp what Josh Marshall calls "the Republicans' bitch-slap theory of electoral politics" — an ugly name for an ugly tactic. Marshall's idea — originally formulated during 2004's Bush vs. Kerry campaign — is that Republican campaign moves often aim to expose opponents as weak by, in effect, slapping them to see whether they'll slap back. A failure to respond exposes you as a weakling; if you won't defend yourself, how will you defend the nation?

Here's how the bitch-slap theory relates to Keystone XL. Obama's pipeline delay represented a rare event in our public life: Street protests led to actual policy change. The president's reversal was, in fact, the one and only signal achievement progressives could point to in an otherwise dismal year that featured, among many other disappointments, Obama's cave-in on tightening smog rules. It was a win for the planet and for a mass popular movement — and therefore it could not stand. The impertinence had to be met with a slap. Otherwise, who knows what demands protesters might start making next?

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And Dave Roberts points out that the Republicans, by pushing too hard, could essentially be handing greens a win:

Remember, Obama's State Dept. has already said in no uncertain terms that if it is forced to accelerate its decision, it will not have time to do a proper environmental review and will thus reject the pipeline. The GOP is forcing State to accelerate the decision. Thus, the State Dept. is going to reject the pipeline.

Again: The GOP has likely ensured that the Keystone XL pipeline will be rejected.

White House communications director Dan Pfeiffer has basically said the same thing on Twitter:

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We'll see what happens in the new year — and we'll see whether voters even notice that Republicans tried to hold their payroll taxes hostage in order to appease the oil industry.