There are many reasons to be bullish about Rand Paul’s unconventional campaign for president. He’s relentlessly courting support from young voters and African Americans, making the explicit case that outreach can translate into wider support. He’s embracing issues that Republicans usually don’t dare touch, such as criminal-justice reform, drug decriminalization, and reining in government surveillance. And based on the early polls, he’s finding himself in solid shape, running competitively against Hillary Clinton and in the top tier of Republican presidential candidates. He even got some good luck, with Nevada’s legislature opting this week to maintain the state’s early caucuses (which benefits Paul) rather than switch to a primary system (that would favor Jeb Bush and Marco Rubio).

But if Paul wants to be president, he’s making a huge strategic mistake, one that’s puzzling some of his GOP allies. By railing against any government surveillance designed to target terrorists and suggesting that U.S. military intervention fueled the rise of ISIS, he’s badly alienating the vast majority of Republican voters who otherwise would give his campaign a long look. At a time when hawkish sentiment within the party is near historic highs and concern over terrorist threats is rising, Paul seems content to thumb his nose at erstwhile supporters—and limit his appeal to only his libertarian base.