Finally, Kaine, like Clinton, is wonky, hard working and cautious. For Clinton, who famously said she’s “cursed with the responsibility gene,” Kaine’s chief attraction—according to media reports—was not his ability to help her win the presidency. It was his ability to be president. As one Clinton confidante told Politico’s Glenn Thrush, “She’s been in the White House, and knows the kind of person who can really do the job … He gives off president vibes. And that’s all that mattered to Hillary.”

“Responsibility,” even dull, nerdy responsibility, is a good thing in a president. If Americans had valued it more highly in 2000, the United States would be in a better place today. But it’s worth noting that Hillary Clinton’s definition of “responsibility” has ideological overtones. It inclines her toward the political center. And the Kaine selection illustrates that, too.

In foreign policy, Clinton has tended to define the “responsible” position as the more hawkish one. Her comment about being “cursed with the responsibility gene,” for instance, came during an explanation of why she wouldn’t support a full withdrawal of US troops from Iraq in 2007. In 2008, she employed the same language to critique Obama’s offer to meet the leaders of Iran and North Korea without preconditions. That, Clinton explained, was “irresponsible.”

It’s not surprising, therefore, that Kaine, Clinton’s “responsible” choice for vice president, is relatively hawkish himself. Like Clinton, and unlike Obama, he backs a no-fly zone in Syria. Like Clinton, he’s criticized Obama’s emphasis on not doing “stupid stuff” because, in Kaine’s words, it also keeps the president from “not doing stuff that’s stupid not to do.”

It’s also telling that Kaine, the “responsible” pick, has more centrist economic views than potential veep candidates Elizabeth Warren, Sherrod Brown, and Tom Perez. Kaine voted for the fast-track trade authority that Obama needs to get the Trans-Pacific Partnership through Congress and recently signed a letter urging the Consumer Financial Protection Bureau to weaken regulations on local banks and credit unions.

To be sure, being a “responsible” centrist Democratic doesn’t mean the same thing today it meant 10 or 20 years ago, when the Democratic Leadership Council remained a powerful force. Since then, the party has shifted left, and so has Hillary Clinton, especially on domestic policy. Still, the Kaine pick suggests that, unlike Obama, who has often prided himself on standing athwart Washington conventional wisdom, Clinton will more often incline towards it. Her choice of Kaine underscores her disciplined, serious, earnest approach to governing. But it also underscores her tendency—so tragically in evidence when she voted to invade Iraq—to run with the Washington herd.

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