IT is disheartening and disconcerting, at the very least, that here we are today — almost exactly eight years after Senator Jim Jeffords left the Republican Party — witnessing the departure of my good friend and fellow moderate Republican, Senator Arlen Specter of Pennsylvania, for the Democratic Party. And the announcement of his switch was all the more painful because I believe it didn’t have to be this way. When Senator Jeffords became an independent in 2001, I said it was a sad day for the Republicans, but it would be even sadder if we failed to confront and learn...