Although I thought President Obama’s speech the other day using Paul Ryan’s budget as a football to kick off the general election was a good one, I concede Ed’s point from his morning post that sitting presidents should not squander their incumbent advantage. Sitting presidents have unique power to generate positive news and to let others do the dirty work.

Ed’s advice to Obama that he should employ a Rose Garden strategy may be conventional, but it’s also wise. The president, as a general rule,  should remain above the fray as long as possible and let his surrogates do the wet work. For example, the timing of the president’s speech may have been premature. No reason to declare the general election season open while Republicans are still in their death throes.

One impression based on years of experience, but not proven, that may explain why Obama feels some obligation to make the attack: He doesn’t always have a choice. Unlike Republicans, Democratic politicians are often loath to expend their political capital helping another, even when that politician is the president, and especially when it involves negative attacks. I have observed this pattern of diffidence from Clinton through Gore to Kerry and now Obama. The Democratic cavalry doesn’t like to ride in the front.