Timothy Noah makes a fair point and follows it with a much more dubious claim:

Much of the Republican resistance to Hagel was based, childishly, on the mere fact that Obama wanted him. But much of it was based on Hagel’s having taken positions on national security issues that his fellow Republicans judged unacceptably dovish—and Hagel isn’t nearly as dovish as Paul is. If Hagel proved unacceptable to the GOP, it’s inconceivable that Paul—who less than one month before the 2012 election published an op-ed condemning Mitt Romney for being too hawkish in the Middle East and too willing to increase Pentagon spending—will ever pass muster. And by “the GOP” I don’t just mean GOP politicians. I mean voters, too. Those Reagan Democrats whom Paul thinks he can woo in California, New England, and the Great Lakes? They’re pretty hawkish. They won’t vote for a candidate who’s weaker on defense than Barack Obama is.

It’s true that Sen. Paul will continue to face significant resistance inside the party on foreign policy, and he will almost certainly face at least as much hostility from party hard-liners as Hagel did if he ever competes for the presidential nomination. Having said that, Noah gets a few things wrong. The first is that hard-line foreign policy is much more important to national Republican politicians and pundits than it is to most Republican voters. There is not that much enthusiasm among rank-and-file Republicans for new wars or a party leadership that seems dedicated to keeping the U.S. at war forever. There is a growing constituency inside the party that rejects both. As long as Rubio and McCain are the most well-known alternatives to Paul, Paul will most likely be well-received by a growing number of Republican voters.

Outside the GOP, there are even fewer Americans interested in the sort of foreign policy that Hagel-bashers prefer. Hard-liners have already contributed to three Republican national losses. It seems likely that the voters alienated by Bush-era foreign policy incompetence and “omni-directional belligerence” are more likely to gravitate back to the party if there is good reason to expect that the next Republican administration will do its best to avoid rather than start new wars, and persuading those voters to come back and to turn out is an important part of assembling a winning coalition. Marco Rubio or Jeb Bush can’t do that, and probably don’t want to try.

Younger Americans that are becoming politically active during the Obama years may not have all the same negative associations with the GOP, but they aren’t very likely to flee from the Democratic coalition unless they think the GOP offers an alternative that is acceptable to them. Continued hard-line hawkishness and militarism will naturally keep driving most of them away. The people outside the current Republican coalition that Sen. Paul is talking about trying to reach are typically young and moderate voters, and these have been the kinds of voters that have responded most favorably to less belligerent and confrontational policies. Paul is mostly talking about voters that have recently abandoned the Republican coalition or have so far refused to join it in the first place. The GOP is weakest with voters under 40, and one of the major reasons for this weakness is that these are the voters that associate Republican rule with the disasters of the Bush years, including Iraq. They have been understandably repelled by the example of Republican governance that they have experienced. It won’t be enough for the next Republican nominee to say that he wants peace and doesn’t want another Iraq. He will have to adopt policies that make those claims seem credible. Once again, Rubio and most of the other would-be 2016 candidates can’t and won’t do that.

Talking about a candidate being “weaker on defense” is not that useful anymore, and one would think that we’d stop talking about the politics of national security and foreign policy this way after the last six years. According to some older conventional standards that Republican hawks still use, Obama could be portrayed as “weaker on defense” than McCain and Romney, but in both elections the majority didn’t prefer the most hawkish candidate. Of course, the idea that greater hawkishness on Iran or Russia has something to do with defending the U.S. is already a bad and misleading one, which is why many Americans already don’t equate greater hawkishness with greater “strength.” When faced with the choice between an overtly aggressive hawk and a less aggressive one, most Americans have preferred the latter twice in a row. Many Americans across the political spectrum want policies that are even less aggressive than Obama’s, and those are a lot of the people that Sen. Paul thinks the GOP should be trying to win over. Whether or not Paul ends up being the one trying to appeal to them, there’s no question that the GOP should heed his advice.