A reader writes:

The most telling line in that item about Shaheen's shot at Obama was this one:

Shaheen said Obama's candor on the subject would "open the door" to further questions.

It's not Obama's drug use that the Clinton people attacked - it's his candor. Even though they've retracted the attack, that choice of emphasis tells you something about their political instincts. When you make mistakes, don't admit them. If there's something embarrassing in your past, deny and obfuscate. Just like kindergartengate, this sort of attack could hurt Clinton more than Obama, precisely because of her distinctive weaknesses.

The supposedly fearsome Clinton attack machine may be this primary's most overhyped commodity. Their attacks are oddly prone to backfire, and it's all because of who Clinton is. Now imagine that kind of botched attack in the heat of a general election. And if their attack machine is inherently flawed… what are Clinton's strengths again?

She's the wife of the last president. Er, that's it.

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