Yesterday, Senators John McCain and Lindsey Graham struck back at Rand Paul’s Wednesday filibuster with bitter attacks on his stand on drone attacks. McCain mocked Paul’s day in the spotlight as “a stunt aimed at firing up impressionable libertarian kids in their college dorms.” Graham was so mad about it that he changed his mind and voted to confirm John Brennan as director of the C.I.A. just in order to send a statement about his support of the drone program that Paul had attacked.

Both McCain and Graham were correct to point out that the filibuster was fought on what is basically a non-issue. As I wrote on Wednesday, while Paul was conducting his filibuster, the Kentucky senator’s real beef is not with the imagined threat of the government ordering a drone strike on a U.S. citizen sitting in a café on U.S. soil. Rather, it is with the war the United States is fighting against Islamist terrorists who continue to pose a deadly threat to the homeland as well as to our friends and interests abroad. Paul’s goal is to withdraw from this conflict and to pretend that it is not one that is being forced upon us by our enemies. That is a dangerous position that deserved the censure of the two GOP amigos.

But it should also be understood that while McCain and Graham were right on the policy, they were dead wrong on the politics. It’s no use pretending that Paul is merely appealing to the margins of the political spectrum as his far more extreme and less politically adroit father Ron did during his presidential campaigns. That Paul’s filibuster was conducted on behalf of a bogus issue doesn’t change the fact that it was an act of political genius that captured the imagination of many Americans who might not ordinarily think much of the senator. Dismissing his achievement only made Paul’s critics look hopelessly out of touch.

The question is not whether the grass roots of the Republican Party were inspired by his stand. They were. How could they not want to cheer a man who took a courageous stand in that manner while so many of their party’s leaders have lacked the guts or the skill to confront the president on many big issues? The question is what those who understand that Paul is wrong on the issue and that he is poised to drag the party down a path that will lead it to abandon its traditional support for a strong America will do about it. If they don’t think of something, it will be the end of the Republican Party’s long-held consensus on foreign policy.

The lesson of the filibuster is that people want to follow a person who leads publicly and courageously. Irrespective of the wisdom of his stand, that is just what Paul did. The willingness of so many other conservative senators—including those like Marco Rubio who don’t agree with Paul’s approach to foreign policy—to flock to the Senate floor while he spoke and offer him support shows they understood what McCain and Graham haven’t figured out. For the pair to manifest disrespect for Paul’s achievement is political stupidity of the highest order. It also makes their gentlemanly decision to forgo a filibuster on Chuck Hagel’s nomination to be secretary of defense look all the more pusillanimous.

Yet the irony here is that while Republicans are excited by Paul’s stand, any decision to change the direction of the party’s take on foreign policy would contradict their desire to improve their electability after their defeat last November.

As much as Paul’s stand inspired Republicans and even generated respect from Democrats, they need to remember that most Americans support the drone policy. They may be sick of the wars in Iraq and Afghanistan, but they don’t share Paul’s disinterest in fighting the “perpetual war” against Islamists because they know the threat is real. They also know that the idea that the only legitimate fighting is being conducted on battlefields between soldiers is hopelessly outmoded.

Obama won re-election in part by bragging about killing Osama bin Laden and chiding Mitt Romney for his disinterest in the hunt for the arch terrorist. Moreover, if Republicans are foolish enough to follow Paul down the road toward embracing a form of isolationism, they will be branded as the weak party on defense and concede foreign policy as an issue to the Democrats for a generation.

Those who wish to save the GOP from this fate can’t let Paul speak for the party on these issues. But if they are to do it they will have to show at least as much guts as he did this week and avoid sounding, as McCain and Graham did yesterday, like cranky old men telling the kids to get off their lawn.