So why did Hillary Clinton take those Wall Street speaking gigs?

The New York Times regularly runs an op-ed feature called “The conversation” in which a liberal (often Gail Collins) and a conservative (often David Brooks) engage in a civil back and forth. Brooks was unavailable this week so Collins discussed the presidential race with Arthur Brooks, president of the righty think tank American Enterprise Institute. It was headlined: “Wait. Which Party Is Imploding?”

My favorite bit was when, unbidden by anything Brooks had said, Collins wondered aloud why Hillary Clinton, who presumably didn’t need the money, took those high-paid speaking gigs from Goldman Sachs and other Wall Street firms in the period just before launching her presidential bid, gigs that have made it so much easier for Bernie Sanders to portray her as a hireling of the millionaires and billionaires on Wall Street. It went thus:

Gail: Sad as it makes me, I have to acknowledge your chortling rights. Mrs. Clinton has a long list of accomplishments and talents that make her an excellent candidate. But she knew when she left the State Department that she’d be running for president and the fact that she took millions and millions of dollars in speaking fees from hedge funds and investment banks is incomprehensible.

Arthur: Studies have found evidence of a certain dopamine allele, prevalent in politicians’ brains, that makes it virtually impossible for them to pass on high consulting and speaking fees. Actually, I just made that up.