Sen. Rand Paul (R-Ky.) catapulted out of his 13-hour filibuster of John Brennan's nomination for CIA chief as a world-changing politician, the new conscience of his party, and a Republican that nonpartisan progressives should love for his defense of our Fifth Amendment rights. (For those who don't remember their civics classes, the Fifth Amendment includes the right to not be murdered at the executive branch's sole discretion, which was the major topic of Paul's marathon presentation last week.)

Paul is center stage now. If he wants to extend his time in the limelight and increase his star power, he needs to play act two and beyond with the same unpredictable political intelligence he showed in his filibuster. The freshman senator has (at least) three problem areas to navigate to extend his new status as a leading national politician and leading 2016 presidential candidate.

1. Democrats and Independents.

As I wrote about Paul last month for the New York Times:

"There's a whole swath of people not getting adequate attention from Republicans or Democrats," Senator Paul told me….These are independent voters who want to seriously cut government spending the way the Tea Party faction does but who also want a "foreign policy more of defense and less offense," as Senator Paul put it, and a "more socially tolerant attitude."…. "If we are ever going to win in California again, or Washington, we need someone who is a libertarian Republican," Senator Paul told me.

Paul has lately written op-eds back in Kentucky recalling the Republican Party's legacy as the party of civil rights for minorities. He told me in February that he intends to do serious outreach to black and Hispanic voters (the Romney campaign claimed only 27 percent of the Hispanic and 7 percent of the black vote). He used his Tea Party-sponsored response to Obama's State of the Union talk to talk sense on immigration. "We must be the party that embraces the immigrant who wants to come to America for a better future," he said. "We must be the party who sees immigrants as assets, not liabilities. We must be the party that says, 'If you want to work, if you want to become an American, we welcome you.'" He told Politico, "We need to figure out how to appeal to the blue-collar voters that voted — that were Democrats that voted for Reagan and I think are drifting back [to the Democrats] because they see us as the party of the wealthy." Paul is very conscious that he needs to widen his appeal beyond an already-existing red-state base.

Paul may have the ACLU's love now, but how many voters does the ACLU really command? Americans don't vote in substantial numbers to support strict constitutionalism. Presidential drone assassinations were no burning concern of the American people before Paul's filibuster. That's why it was so inspiring: It arose from a curious and unique passion, one that was clearly not politics as usual. The kind of politicians Democrats tend to vote for wanted nothing to do with what they saw as Paul's annoying stunt.

Superficial respect for the concerns of the ACLU is part of an elite Democratic zeitgeist. But when most Democrats and progressives think of Rand Paul, it won't involve the Fifth Amendment or endless wars at home and abroad. They will think about abortion, a refusal to raise taxes on the rich, and neglecting what they see as government's duty to take care of people. Opposing crony capitalism is nice enough, but disaffected Democrats see the GOP as the "party of the wealthy" because of its refusal to raise taxes on rich people. The libertarian educational project needs to make more progress before many independent-leaning voters will stop believing that that the government must penalize the rich to help the less-well-off. If and when Paul switches from a refreshing outlier or libertarian maverick to becoming the GOP standard-bearer, any progressive support will likely disappear.

Paul is doing the best he can to appeal beyond a core libertarian or Republican base. Yet it seems unlikely that any amount of civil liberties, peace, or opposition to crony capitalism will satisfy most independents or Democrats over the longer haul. Their visions of government's purpose are just too antithetical to Paul's.

2. Republicans.

Paul's libertarianism doesn't just create a gap between him and Democrats and independents. It causes problems within his own party. To be sure, Paul got a surprising amount of support from his Republican colleagues during the filibuster. But the big surge came only after hour three, and only after the filibuster's popularity was obvious. The support may have been opportunistic, aimed at slapping down Obama, and limited to the narrowest part of Paul's concerns. But it does matter that other senators saw standing with Rand as a political plus.

Paul went beyond civil liberties as the day went on, and started ranging into the principled libertarian "extremism" that had gotten him into trouble back in 2010, when he criticized civil rights legislation for redefining private and public spaces. As the filibuster wore on, Paul pushed into territory where most of his Republican colleagues would be loath to follow. He conjured up some serious libertarian juju—like that we are not a democracy and that that's a good thing; that the Lochner decision was good because it restricted majority power in the name of 14th Amendment rights; he namedropped specifically libertarian heroes such as Hayek (for the rule of law) and Lysander Spooner (for his abolitionism, though not his belief that the Constitution doesn't mean we have any contractual obligation to obey the state).

But Paul undoubtedly remembers how tough it is to be in the national spotlight and to constantly be called on to defend the least popular liberatarian positions and to play the role of the great non-compromiser. It's wearying to insist on absolute fidelity to principles and to never back down. This likely explains the disappointing denouement to the filibuster, which was Paul's quickly taking "no" for an answer from Attorney General Eric Holder.

Holder sent a letter after the filibuster dutifully claiming that the president lacks "the authority to use a weaponized drone to kill an American not engaged in combat on American soil." Yet given the looseness of what it means to be engaged in combat, Holder's response hasn't satisfied many libertarians.

Paul acknowledged in a Washington Post op-ed that Holder's answer was flawed ("the administration took too long, and parsed too many words and phrases, to instill confidence in its willingness or ability to protect our liberty"). Still, he avoided turning from brave iconoclast to impossibly paranoid kook. At a certain point, he seemed aware his GOP brethren were not going to follow him to what could too easily be called black helicopter land after Holder's letter. Paul decided to just say "hooray" and that he was "quite happy" and let Brennan go forward to his new CIA job—without Paul's vote.

After the filibuster, Paul went to a meeting of the Club for Growth, a big-money funder of Republican candidates who claim to privilege small government and low taxes above all. National Review reports from that meeting that Club donor George Yeager praised Paul for having "broadened his appeal to include three issues that 75 percent of the American people agree with….He wants a balanced-budget amendment, term limits, and a questioning of mindless nation-building overseas."

It would be an extraordinary turn if Yeager's vision of a successful Republican candidate can win with the GOP at large. Since 9/11, the Republicans have been dedicated precisely to nation building and a global war on terror that sees every moment of Middle Eastern unrest as an opportunity for the next invasion of a foreign country.

In fact, one of the most amazing things about the filibuster is that it could have been aimed 100 percent at George W. Bush and the policies the Republican party and the conservative movement have urged for most of the 21st century. Republican National Committee Chair Reince Priebus was calling on all his party's senators to join Paul near the end of the filibuster. The National Republican Senatorial Committee raised high five figures off of the publicity surrounding it. Influential Iowa right-wing talk radio man Steve Deace declared that Paul would win Iowa if its caucus were held now.

Ben Shapiro at Breitbart.com tried to claim the day as a victory for "conservatism," but it isn't a conservatism anyone would recognize from the past two decades or more. Yet Paul now has the love of leading figures of the conservative opposition to the GOP mainstream, from Glenn Beck to Rush Limbaugh (who mused that Paul might succeed in making the party "suspicious of interventionism, suspicious of Islamic democracy building, suspicious of financial and military support for dubious regimes.")

How long can the lovefest last? Once the mass Republican audience—especially Mitt Romney voters—really thinks about the implications of Rand Paul and his ideas, the post-filibuster love may sour. Paul's chief of staff Doug Stafford told Business Insider, "Rand is one of the only people who can speak to libertarians, social conservatives, as well as your average mainstream Republican voter." In theory, yes.

But even in areas where Paul's libertarianism shouldn't be too controversial—like his five-year path to a balanced budget—hardly any of his political colleagues are willing to play along, and there's no mass constituency forcing them to. It's not likely the rest of his party—whether rank-and-file voter or office-seeking politician—will get enthusiastic about his attempts to curb the federal drug war either.

Paul's problems with Republican orthodoxy run deeper still. In order to keep her head from exploding from cognitive dissonance while remaining on the new right side of Republican history, the Washington Post's right-wing columnist Jennifer Rubin praised Paul's filibuster by claiming that he "wasn't attacking the war on terror."

But Paul absolutely was attacking the war on terror, which leads to a third problem.

3. Foreign Policy.

This filibuster was mostly reported as a civil liberties story, one about Americans' right to be free from arbitrary attack from their government. That's how Paul framed it himself. But at the heart of Paul's peroration was something deeper than questioning executive authority to kill Americans at will. His talk lamented the troubled morass that more than 12 years of recklessly overreaching warmaking in the name of fighting terror have wrought. Paul attacked the loose way we use drones overseas, talked of likely blowback from our reckless killings in Third World villages and cities, condemned a war against an impossible-to-identify enemy, and railed against a war without end in space or time.

As reported by Slate's David Weigel, the senator told a group of reporters in a meeting at National Review's D.C. offices:

"All of this stems from a very expansive understanding of the use of the Authorization of Force in 2001. I think most of the people who voted on that, when they did, thought we were voting to go to war with the people who attacked us on 9/11. They didn't realize it was a war without geographic limits and without end. And that's the problem with saying, oh, we're just going to give up—while we're involved in war—we're going to give up some of our liberties here at home. This is a war that has no end and it's hard to stop."

These are important things to care about. But they aren't a likely recipe for political success. Polls show that most Americans are tired of the endless overseas wars. But in a post-draft America, foreign affairs are a very low political priority, with only 5 percent or so calling them a major electoral concern. Even Paul's supportive filibuster colleagues were pretty careful to stick to the Fifth Amendment and presidential authority when they spoke. They were not joining Paul in his larger critique of interventionist foreign policy.

There's no question that the filibuster made Rand Paul a star. The Twitter hashtag #standwithrand strode through the social media worlds like a colossus—top trending on Twitter! Over 200,000 Google searches! But for the establishment and the old media, it was almost a non-event. The very long front-page New York Times story about the Brennan nomination the day after the filibuster did not mention Rand Paul or the reason for the filibuster until the 16th paragraph, long after the jump. The Sunday news shows universally saw Jeb Bush as a more newsy interview "get" than Paul.

In the heat of the moment, some overenthusiastic movement watchers (like me!) saw the GOP changed irrevocably in a Paulian direction. It felt bracingly fresh to those of us watching it unfold, and watching everyone else we knew watching it unfold, commenting on the wonders we were seeing and the wonders of how we were all communicating about what we were seeing. The meta-loop opened to infinity when the commentary became the story and Sen. Ted Cruz (R-Texas) read pages of Twitter praise aloud to the nation.

While the filibuster was important, there's no evidence yet it made Rand Paul a lasting household name. Or that people who are vaguely aware a senator talked for hours about something or other ("drones on… and on…" as CNN witlessly put it) could adequately explain what he was concerned with and why. Even if they access their news online or via smart phone, most Americans still get their news the semi-old-fashioned way, from legacy print or TV institutions.

Which isn't to scant the effect of Paul's filibuster. Rand Paul is a contender for the 2016 presidential race. Common wisdom has it that the Republican presidential nomination goes to whoever is next in line. Based on the popular vote from the 2012 primary season, that would mean Rick Santorum (and good luck with that, GOP). But in the real currency of nomination, delegate votes on the floor of the RNC, the runner-up in 2012 was Ron Paul. Perhaps his son can be heir to that position, if he can just navigate three small problems with the same aplomb he exhibited on filibuster day.