WASHINGTON

Successful economic ideas usually end up being taken too far.

Democrats dominated the middle part of the 20th century, thanks in part to their vigorous response to the Great Depression. They used the government to soften the effects of the Depression and to build the modern safety net. But they failed to see the limits of the government’s ability to manage the economy and helped usher in the stagflation of the 1970s.

Ronald Reagan then came to power promising to cut taxes and unleash the forces of the market. And the Democrats spent the next dozen years struggling to absorb the lessons of their failures.

More than a few people believe the Republican Party is in a similar place today.

When I asked Dale Jorgenson, the eminent expert on productivity (and a Republican), what had been the positive aspects of President George W. Bush’s economic policy, Mr. Jorgenson said, “I don’t see any redeeming features, unfortunately.” After Republicans opposed the stimulus package this year, The Financial Times, not exactly a liberal organ, called the party’s ideology harebrained. When Olympia Snowe was recently explaining why she might be the only Republican senator to vote for health reform, she suggested it was because her party had moved so far to the right.

But perhaps the most persistent  and thought-provoking  conservative critic of the party has been Bruce Bartlett. Mr. Bartlett has worked for Jack Kemp and Presidents Reagan and George H. W. Bush. He has been a fellow at the Cato Institute and the Heritage Foundation. He wants the estate tax to be reduced, and he thinks that President Obama should not have taken on health reform or climate change this year.