A tunnel at the end of the light

Somewhere, some how, sometime, this thing is gonna end.

The most powerful economy America has ever seen will lose some steam.

That was the message last week from Alan Greenspan, the closest thing our planet has to a real-life Yoda (Think about it: wields great power with no visible effort, speaks in vague riddles, wispy evidence of hairline).

Mr. Greenspan, like the rest of us, presumably spends most of his time wondering whether he can play hookey on opening day for "The Phantom Menace," but he spends his spare moments protecting our financial universe.

And he apparently senses a disturbance in The Force.

The Fed chairman hinted last week that the US economy cannot maintain its warp speed without busting a gear in the hyperdrive.

He said the recovery in Asia is fragile; Japan still has problems, Brazil looks iffy, etc., And he said - rather, suggested - that if the American workforce slows its gains in productivity, inflation could become a problem.

Greenspan has done this before - tried to let some air out of a stock market that last week zapped 11000.

And, as before, he temporarily derailed the Dow midweek.

But the productivity argument becomes a tough one. Because the remarkable productivity in the US gains have come largely from corporate use of technology.

And technology has a new friend in the Internet, a force yet to achieve full measure.

Consequently, it now takes investors just a few hours to decide that when Greenspan grabs a light saber, it's mostly a light show.

And they send stock indexes to new highs, as they did on Friday.