Carlo Allegri / Reuters

There are three obvious downsides to Marco Rubio’s decision to run for reelection to the United States Senate. First, he’s flip-flopped: As recently as May, he promised not to enter the race. Second, even if he wins, he’ll spend the coming years taking votes that could cause him problems in a presidential campaign. Or, if he skips those votes, he’ll be slammed for his absenteeism, as he was by his primary opponents this year. Third, and most importantly, if he loses his reelection bid, his political career is likely over.

Still, his decision to seek reelection was wise. That’s because if he wins, he can run for president as the guy he really is.

On its face, the lesson of 2016 is that it’s better to seek the Republican presidential nomination from as far away from Washington as possible. By this logic, Rubio should vacate his Senate seat and spend the years leading up to the 2020 campaign railing against the Republican establishment, a la Donald Trump.

But there are two problems with that plan. First, Rubio isn’t a mega-celebrity; he won’t be able to command massive media attention outside of the Senate. “Generally, it’s always harder for conservative leaders to be really influential without any official role,” noted a Republican strategist who took part in discussions with Rubio about his decision to run. (He spoke on the condition of anonymity because of the confidential nature of those conversations.) Yes, Rubio can go on Fox News, this strategist said, but he “runs the risk of being Mike Huckabee,” who could never get back to center stage after dropping out of the 2008 presidential race.

Exacerbating that problem is Rubio’s likely competition. In Ted Cruz, Tom Cotton, and Ben Sasse, he faces three smart, young, ambitious foes, all of whom can use their Senate seats to overshadow him. Cruz has already built the GOP’s most formidable ground operation. Sasse has made himself a hero among the #NeverTrump crowd. And Cotton, an Iraq War veteran and militant Iran deal opponent who sits on the Senate armed-services and intelligence committees, could eclipse Rubio as the favorite of the Bill Kristol-led, neo-imperialist set.  

The second, and even bigger problem with Rubio leaving the Senate and running against Washington is that this narrative is not true to who really is. “It’s hard to run as an outsider if you’re if a former insider,” said the strategist who talked to Rubio. “It’s not authentic.”

It’s inauthentic not merely because Rubio has already served in the Senate. It’s inauthentic because of what Rubio believes. His policy inclinations—pro-immigrant, pro-globalization, and pro-military intervention—echo those of the GOP donor class. That’s a big reason his presidential candidacy generated suspicion among the more isolationist, nativist conservatives who dominate talk radio. If he tries to run as the candidate who hates Washington the most, he’ll look about as genuine as he did in the final days of his 2016 campaign when he tried to out-potty-mouth Trump.  

Rubio’s true passion is national security. Unlike Cruz, he didn’t grow up with strong convictions about domestic issues. His grew up loving Ronald Reagan for one reason only: Reagan stood up to communists like Fidel Castro. Despite missing tons of Senate votes, he frustrated his political advisors by devoting too much time to his work on the foreign-relations and intelligence committees.

Staying in the Senate gives Rubio the chance to emerge as Hillary Clinton’s most high-profile national-security critic. Doing so would cement his ties to the GOP’s hawkish donors and prevent him from being eclipsed by Cruz, Cotton, or Sasse.

Given the lessons of the Trump campaign, it’s far from clear that Dick Cheney-style national-security hawkishness will be the future direction of the GOP. But people who have talked to Rubio argue that running as a national-security expert is smarter for him than running as an anti-Washington outsider—not because it fits the identity of the GOP, but because it fits the identity of Marco Rubio.

That strikes me as correct. At times during the 2016 campaign, Rubio looked like the GOP’s John Edwards: an attractive, energetic, eloquent guy who lacked a core. Overcoming that image is crucial if he ever wants to be president. And staying in the Senate gives him a better chance of doing it.

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