When the Air Florida plane crashed in the Potomac last week, there was very little that police and rescue squad personnel could do. The weather and the water conspired to make rescues nearly impossible. That even five passengers were rescued was an achievement.

We may not be so fortunate next time if there is a repeat performance of the scene that played out along the downtown 14th Street strip just after the crash.

As dozens of D.C. police cruisers and ambulances attempted to reach the scene of the crash from all over the city, they were stymied by a near-gridlock mess all along 14th Street -- from Thomas Circle all the way to the bridge.

In many cases, according to eyewitnesses, emergency vehicles had to drive along sidewalks to get by. Many officers were delayed by as much as 15 minutes, at a time when every instant counted. That is why most of the first official vehicles to reach the wreckage came from Virginia, even though the scene of the crash technically fell within the jurisdiction of the D.C. police and fire departments.

This is not to accuse motorists of refusing to cooperate with emergency vehicles. The trouble was that motorists couldn't have gotten out of the way even if they had wanted to. Because a few clowns had entered a few intersections before they should have, there was nowhere to go.

The problem was what it always is during Crush Hour: impatience, selfishness and a failure to see the forest for the trees.

Several latter-day John Waynes, who think the Constitution entitles them to drive wherever they please, decide that trying to save three car lengths is worth the chance of getting marooned in the middle of an intersection. It doesn't take too many of these adventurers to cause the mess we had last Wednesday.

A reminder: It is against the law to enter an intersection anywhere in the Washington area unless you are able to get all the way through it before the light turns red.

I don't want to hear how green the light was when you started. Neither will the judge. When you can see the next block jammed to the gills, play it conservatively. Just stay where you are for a minute or so.

Nor do I want to hear how late you are for dinner. You aren't the only one, pal. Look around you. Those other folks are in the same jam..

As far as plane crashes go, I hope there's no "next time." But if there is, any of us caught in traffic near the scene must remember to make room, and to preserve a way to do that. It's never worth it, crash or not, to try to outfight fellow motorists for a small hunk of the road. And in a crash situation, it could make a life-or-death difference.