Syndicated columnist Charles Krauthammer said Tuesday on “Special Report with Bret Baier” that Sen. Rand Paul, R-Ky., who today announced his candidacy for president, has huge obstacles to overcome in the foreign policy realm.

"The Obama foreign policy has collapsed, and whatever name you want to put on Paul's position, isolationist or non-interventionist, he's without a doubt the one Republican who’d be running who is closest to Obama in his view of foreign policy," Krauthammer said.

"Arguably, he's to the left of Obama on NSA, on surveillance, on the use of drones, essentially, on the war on terror," he said.

Krauthammer said Paul’s stated view that "the goal is always peace, not war" simply isn’t right.

"Our objective is always national security. And sometimes you can get it on the cheap, and sometimes you can’t," he said.

On campaign strategy, Krauthammer said if Paul  tacks to the right and tries to show he’s tough on foreign policy, his authenticity will be called into question.

"I think essentially he has a hill he cannot climb," he said.