WASHINGTON -- Baby Boomers have pumped up the global economy with their profligate ways for nearly two decades. It's been a great party. Now the music's over.

Generalizations about the 79 million people born between 1946 and 1964 are overdone and easy to debunk. Boomers went to Woodstock, voted for George McGovern and, so the thinking goes, cared deeply about the Rolling Stones. Boomers also helped put Ronald Reagan and fellow Boomer George W. Bush in the White House and turned Nashville into a cultural capital.

But...