The American Century just ended. This was the phrase coined by Henry Luce, which so aptly described America as the modern-day colossus, more powerful than any nation had ever been. Wednesday night, President Obama said that power had reached its limit. He was bringing 10,000 troops home from Afghanistan. The war was not finished, but we are.

“America, it is time to focus on nation building at home,” the president said.

There it was, the theme of the speech. We had done what we could in Afghanistan, and there was, of course, more to do. But the purse was empty and the nation was tired -- this is me, not Obama, talking, but he said much the same thing. “We must be as pragmatic as we are passionate; as strategic as we are resolute,” Obama said. In other words, we are going to pick our fights more carefully, and when we do, we can use the new weaponry of drones and the units of SEALs and such. No need for massive armies anymore. From the president’s mouth to God’s ear, I would add.

I have heard this speech before. I heard echoes of Richard Nixon explaining “Vietnamization.” Gonna turn the war over to our stolid allies. We put them on their feet. We trained them. We supplied them. We schooled them at our elite military academies. They looked splendid in their uniforms. But when the U.S. pulled out, South Vietnam collapsed. It will happen again in Afghanistan. I think Obama knows that. He fought this war -- authorized the West Point surge -- because he did not know how to get out. Now, he does. As any previous president could have told him, it’s by getting out.

Somewhere in the Obama speechwriting shop is someone with a tin ear. Having raised the specter of Vietnamization, Obama came close to mimicking Robert McNamara’s famous and klutzy line about the Vietnam war, “light at the end of the tunnel.” He said, “And even as there will be dark days ahead in Afghanistan, the light of a secure peace can be seen in the distance.” I hope so. But this secure peace will not hold a day. Even George McGovern’s refrain from his 1972 acceptance speech at the Democratic convention -- “Come Home America” -- was echoed here as a call to turn inward.

McGovern’s call was stirring and profound, and even though Nixon beat him, America did come home. We were a tired and divided nation, and we hated one another with a fury that no one should forget. The Vietnam war was long and bloody, over 50,000 dead, and it almost seemed as if no one could remember why we were fighting -- or for what.

Something similar has happened in Afghanistan. Bin Laden is dead. Al-Qaeda has been riddled by drones. The job is done, or done enough, and we are broke and in need of some R&R. Obama surely knows his history and does not want it repeated -- neither as tragedy nor as farce. We are not Henry Luce’s America -- not because we no longer want to be, but because we no longer can be.