There has been a spike in support for the war in Afghanistan since President Obama’s West Point speech. A new Quinnipiac University poll finds public backing for the war effort has shot up by 9 points over the past three weeks. Now 57 percent of voters say fighting the war is the right thing to do. The public is split on Obama’s handling of the war effort, 45-45 percent, but that’s a big jump from three weeks ago, when 49 percent disapproved and only 48 percent approved. And fully 58 percent of those surveyed back the decision to send 30,000 more combat troops, even though 45 percent do not believe he will keep his promise to begin withdrawing them in July 2011 (vs. 40 percent who believe him).

The White House should revel in this public approval, which comes as a welcome contrast to the president’s overall slippage in support (he’s down to 48 percent job approval and 46 percent disapproval in the RealClearPolitics average of polls). But no one should take such continued backing for granted. There will be tough days ahead, with Americans suffering casualties, big terrorist attacks occurring in Afghanistan, and all the problems that attend a war effort against a tough, determined, resilient foe. To keep public support high, Obama needs to keep stumping. The West Point speech can’t be a one-off. He needs to wage the same kind of sustained campaign to drum up support for defeating the Taliban as he has for passing health care. Already he’s had more success in making the sale on Afghanistan; imagine what a sustained level of effort — of the kind we didn’t see after the major Afghan announcement in March — could achieve.