Yesterday, AARP ran a full-page ad in The New York Times asking Congress and the president to agree on a prescription-drug benefit under Medicare. One line from the ad jumped out at me: "Every effort should be made to reduce gap in coverage."

As Robert Pear's story in yesterday's Times explains, the Republican proposal for prescription drugs "would leave a big gap for some people. Under the Senate bill, for example, Medicare would share drug costs up to $3,450 a year, but would not provide further coverage until a beneficiary's annual drug costs reached about $5,300."

Why does the GOP plan in the Senate do that? I guess I understand the notion of covering both ordinary and extraordinary expenses, but why exclude what's in the middle? What's the logic behind that?

Now, look at the wording of that line from the AARP ad: "Every effort should be made to reduce gap in coverage." It's almost as if the AARP thinks this gap is some sort of natural phenomenon, something like cancer or tornado damage that we simply can't eliminate but should do our best to minimize. It isn't. People made this gap. It doesn't have to exist at all.