I think Brad DeLong is the author of that phrase, to describe the process of holding earlier assessments to the hard test of later outcome. Riffling through some old computer files this morning, I found a script for a radio broadcast I wrote on the occasion of the 100th day of the Obama presidency. What do you say? How does it hold up?

The original "hundred days" ended with Waterloo—so it's a low bar to do better than that. In his first hundred days, President Obama has done a great deal to restore public optimism and confidence at home. Half of Americans now say the country is on the “right track,” the best number since the liberation of Baghdad in April 2003. Optimism matters. But it's not very tangible nor is it likely to be very enduring in the absence of more solid achievements. And here President Obama’s record is more troubling.

The restoration of confidence may remind some of Ronald Reagan’s morning in America. But except for a blip after John Hinckley’s assassination attempt, Ronald Reagan’s job-approval numbers only exceeded 60% after his policies had gone into effect and delivered results in 1984, 1985, 1986 and 1987. With Obama at 69%, it seems to be reward first, achievement later. The restoration of confidence may remind some of Ronald Reagan’s morning in America. But except for a blip after John Hinckley’s assassination attempt, Ronald Reagan’s job-approval numbers only exceeded 60% after his policies had gone into effect and delivered results in 1984, 1985, 1986 and 1987. With Obama at 69%, it seems to be reward first, achievement later—if ever.

The US is wracked by the worst financial crisis in decades. Experts estimate the bad [household] debt in the economy at anywhere from $1.5 to $3.5 trillion.if ever.

President Obama's economic plans are all based on the assumption that the correct figure is at the low end of that range. That's the assumption that lies behind every one of his key economic decisions,from the $800 billion in stimulus to his plans to proceed fast with a big new healthcare program and cap-and-trade for carbon emissions.If the president is right, then the United States can probably afford his plans—just.

If he's low-balled it, then the United States will find itself a year or two from now seeking to borrow another trillion on top of debt levels that have already hit peacetime highs.The most important of his decisions are already locked in—and the others are just minutes away.President Obama promised dramatic change. But in one way, he follows so many of his recent predecessors: on the eve of Day 100, he has gambled his presidency on his affair with that always popular Washington belle: Rosy Scenario.