* Obama’s political challenge on Afghanistan: Scott Wilson and Karen DeYoung make the key point about Obama’s Afghan speech tonight: The hard part for Obama won’t be to sell the public on his plan to withdraw 10,000 troops this year and another 23,000 next year. Rather, the real difficulty he faces tonight is to persuade the public that continuing the war at the level he wants to is worth the cost in money and lives.

Though the hawks will insist otherwise, Obama’ real political vulnerability on Afghanistan will reside in the question of whether he’s winding the conflict down fast enough. After all, as Sam Youngman points out, there will still be tens of thousands of American troops in Afghanistan come Election Day 2012 — and Obama will have to explain why we’re still bogged down in that part of the world some 11 years after the 9/11 attacks. That’s the prism through which to view tonight’s speech.

* Time to wind down Afghan war and spend the money creating jobs here: One thing increasing pressure on Obama to wind down the Afghan commitment even faster is the growing awareness that we’re spending huge sums on the war while the unemployed languish at home. This quote from the Center for American Progress’s Brian Katulis captures the situation perfectly:

“Do we really need to be spending $120 billion in a country with a G.D.P. that’s one-sixth that size? Most Americans would be shocked to know that we’re spending that kind of money for jobs programs for former Taliban, and would wonder where are our jobs programs for Detroit and Cleveland?”

* Terrible numbers on the economy: Today’s Bloomberg News poll is rough for Obama, particularly this:

By a 44 percent to 34 percent margin, Americans say they believe they are worse off than when President Barack Obama took office in early 2009, when the U.S. was in the depths of a recession compounded by the September 2008 financial crisis and the economy was losing as many as 820,000 jobs a month.

Get ready for a lot of talk about how the time is ripe for Republicans to reprise Reagan’s line against Carter: “Are you better off than you were four years ago?”

* Pawlenty’s first ad takes shot at Romney over health care: The 2012 GOP primary is off and running as T-Paw goes up with his first TV ad in Iowa touting his “conservative” solutions as Minnesota governor.

The key line: The claim that he “passed health care reform the right way. No mandates. No takeovers.” That, of course, is a shot at Romneycare’s mandate, which T-Paw is going to target with the dreaded ”government takeover”slur.

* Huntsman piles on Romney: Jon Huntsman is now also going after Romneycare, claiming that the Massachsetts model (with mandate) shows that Romney “has little credibility” on the health care issue.

Key takeaway: The effort to bring Romney down among GOP primary voters by hammering his health plan is now fully underway.

* Al Gore faults Obama on global warming: This is a very big deal: Gore is set to weigh in with a 7,000 word Rolling Stone piece calling out Obama for failing to lead on climate change.

While this is an important development, this will likely get overshadowed by other issues (Afghanistan, the economy) another measure of just how far off the radar climate change has drifted.

* Tensions running high over New York gay marriage vote: With the measure still one vote short of passage in the state senate, undecided GOP senators remain on the fence even as New York Governor Andrew Cuomo urges the senate to vote before adjourning. This could be decided this week.

* Will Huntsman’s outbreaks of common sense doom presidential candidacy? Good catch by Sam Stein, who notes that Huntsman has now broken with GOP orthodoxy by saying he would respect a New York State decision to legalize gay marriage — without adding that he supports a Federal ban. It’ll be really interesting to see if this costs him in the GOP primary.

* Huntsman’s fact-free announcement speech: Hilarious: His speech was so devoid of meaningful assertions that Post fact-checker Glenn Kessler pronounces it virtually un-fact-checkable.

Key takeaway: Compared to the other GOP candidates, whose announcement speeches were packed with lurid and hallucinogenic falsehoods, this is a signal that Huntsman is not trying to win over the base with any outsized or crazy anti-Obama rhetoric. This guy is toast!

* No, tax cuts don’t lead to a rise in revenues: Paul Krugman has a very vivid chart deflating the ubiquitous right-wing myth that the Reagan tax cuts led to a huge revenue spike.

Key conclusion: “There was no Reagan revenue miracle; growth slowed. There was a Clinton miracle.”

* Today’s installment in the Darrell Issa chronicles: Rep Issa, who oversees the House GOP investigations arm, has gotten lots of attention with his crusade against the Obama administration over a controversial operation targeting Mexican gun-runners.

But now a great Post story reports that he was fully briefed on the program in 2010 and didn’t raise any objections.

* Postscript: Donald Trump played media for chumps: Now that we learn that NBC agreed to pay Trump $65 million per year to keep his reality show going, rather than run for president, can we all admit that anyone who took his presidential aspirations seriously was the victim of a big con job?