Rand Paul moved Tuesday to reassure hawkish Republican primary voters that his libertarianism stops at the water’s edge.

Recognizing the biggest threat to his 2016 prospects, the Kentucky senator attempted to blunt long-standing charges from inside his own party that he is an isolationist and to the left of President Obama on foreign policy. In a speech declaring for the White House, Paul vowed to support a robust military and get tough with “Islamic extremism,” while signaling opposition to the Obama administration’s negotiated framework to limit Iran’s nuclear weapons program.