U.S. Republican presidential candidate Mitt Romney has yet to announce his vice-presidential running mate. (JONATHAN ERNST/REUTERS)

The great irony of the vice-presidential selection process is that the decision about who could be a heartbeat away from the presidency seems to have everything to do with electability and very little to do with leadership.

Running mates, by and large, are publicly discussed during the “veepstakes” as a way of balancing the ticket, or complementing the candidate. One might help broaden geographic  or ideological appeal: A northeastern liberal (John F. Kennedy, Michael Dukakis) chooses, say, a more conservative running mate from Texas (Lyndon B. Johnson, Lloyd Bentsen). Another might help emphasize a key campaign platform: Jack Kemp, the thinking went, would bolster Bob Dole’s standing on economic issues, while Al Gore reinforced Bill Clinton’s attributes as a young southern centrist from the baby boomer generation.

Many analyze Mitt Romney’s current search through the same electability prism.

Sen. Rob Portman (R-Ohio) has the Washington credentials Romney is missing, for instance, while former Governor Tim Pawlenty, the son of a truck driver, could help him build credibility with the average Joe. Marco Rubio has gotten lots of attention for being a Hispanic senator from a big state, Florida.

But these are just lines on a resume. What we rarely hear about are the leadership capabilities of those under consideration—what kind of decision-makers they are, how persuasive they would be as a congressional closer, or the type of sounding board they would provide the president in solving tough, consequential dilemmas.

Yet if there’s a threshold trait Romney, like any presidential nominee, should look for in a running mate, that’s it: leadership. A VP candidate has to be presidential.

A vice president has to be able to assume the presidency seamlessly if tragedy strikes but, in normal times, be willing to walk into the Oval Office and give the president unwelcome advice in a persuasive way.  He or she must be able to interact with world leaders as a skillful diplomat.

And yet the vice president must also have the discipline and willingness to subordinate his or her ego to serve another, not a common trait in those who have risen to the highest levels of our political system. That’s true of a vice-presidential candidate, too, who must echo the standard-bearer’s themes and celebrate his virtues while attacking the opposition—and still appearing a plausible president.

Too often we talk about campaigning and governing as though they involve two completely separate sets of traits. Yet some of the best recent running mates were also the ones with the best skills for the White House job, not just getting the votes.

Vice presidents like Walter F. Mondale, George H. W. Bush, Al Gore, Dick Cheney and Joe Biden succeeded in both the campaigning and governing roles. Meanwhile, freelancing vice presidential candidates like Sarah Palin or John Edwards, picked largely for their perceived electoral attributes, were ultimately no more helpful on the campaign trail than they probably would have been in office.

It takes special skill to perform the role of No. 2 well, pre- and post-election. A good choice must bring substantive strength, expertise and relationships, yet be adaptable enough to respond effectively to someone else’s leadership structure and style and to work in tandem with their team. 

There are political costs to choosing a running mate who cannot plausibly lead well in both scenarios. A poor choice impugns the skill and judgment of the selector and alienates voters who can’t fathom a mediocre leader being just a heartbeat away. Spiro Agnew’s presence complicated Richard M. Nixon’s 1968 presidential run. And the Palin choice made John McCain appear impulsive and willing to abandon his own campaign refrain that experience matters. Voters are smart enough to know when a VP is on the ticket just to target a particular bloc of voters.

Yes, the timing of the selection process makes it nearly inevitable that Romney will choose a running mate who might help him become, rather than succeed as, president. He, like all candidates, will make the choice while preoccupied with winning the election, not figuring out how to govern.  

Most presidential candidates can’t visualize the structure of their administration the summer before the election, and therefore can’t see how a vice president’s style would fit in. And though much may be known about potential running mates, it’s hard to anticipate the range of leadership assets a particular VP can contribute.

But we’re talking about the person who may be second in line to lead the most powerful country in the world. The VP selection is the first presidential decision most standard-bearers make, telling voters plenty about their values. Choosing someone of real substance who can lead, follow and compensate for weaknesses of the presidential nominee is good governance—and, ironically, good politics.

Joel K. Goldstein is a professor at the Saint Louis University School of Law. He is the author of numerous works on the vice presidency.

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