The people who brought you the Barack Obama birth-certificate hullabaloo now have a new target: Sen. Marco Rubio of Florida, a man often speculated to be the next Republican vice presidential nominee. While they’re at it, they also have Bobby Jindal, the Republican governor of Louisiana and perhaps a future presidential candidate, in their sights. …

The good news for the birthers is that this suggests they were going after Obama, whose father was a Kenyan national, not because of the president’s political party. The bad news is that this supports the suspicion that they were going after Obama because of his race. …

But the wild new turn the birthers have taken should serve as a timely reminder to Republican leaders that they need to push back more forcefully against the angry and the unstable in their ranks. Too often, they have done the opposite. Jindal, for example, encouraged the birthers this year when he announced his support for legislation that would require candidates for federal office to show proof of their U.S. birth before being allowed on the ballot in Louisiana. It was, as many pointed out, a sad gesture for a man born Piyush Jindal.