To what extent should US citizens loses their constitutional right in the "war on terror". Can US citizens be apprehended without charges? Killed by drones? On US soil?

John Brennan, Obama's nomination to run the CIA, refused to disavow even that last question. In response, Senator Rand Paul courageously, and single-handedly sponsored a filibuster in the Senate to block Brennan's appointment.

Wired reports 11 Years Later, Senate Wakes Up to War on Terror's 'Battlefield America'

Sen. Rand Paul's filibuster will inevitably fail at its immediate objective: derailing John Brennan's nomination to run the CIA. But as it stretches into its sixth hour, it's already accomplished something far more significant: raising political alarm over the extraordinary breadth of the legal claims that undergird the boundless, 11-plus-year "war on terrorism."

The Kentucky Republican's delaying tactic started over one rather narrow slice of that war: the Obama administration's equivocation on whether it believes it has the legal authority to order a drone strike on an American citizen, in the United States.

Paul recognized outright that he would ultimately lose his fight to block Brennan, the White House counterterrorism chief and architect of much of the administration's targeted-killing efforts.

But as his time on the Senate floor went on, Paul went much further. He called into question aspects of the war on terrorism that a typically bellicose Congress rarely questions, and most often defends, often demagogically so. More astonishingly, Paul's filibuster became such a spectacle that he got hawkish senators to join him.

as the filibuster picked up more and more media attention -- and especially social-media attention -- hawkish senators began joining in. Sen. Marco Rubio (R-Florida) praised Paul's efforts at compelling transparency from the White House. What Paul is arguing is "no less important than our Constitutional government itself," said Sen. John Cornyn (R-Texas), no dove.

It would be foolish to presume that Paul's moment in the spotlight heralds a new Senate willingness to roll back the expanses of the post-9/11 security apparatus. Rubio, for instance, stopped short of endorsing any of Paul's substantive criticisms of the war. But Paul did manage to shift what political scientists call the Overton Window -- the acceptable center of gravity of discussion.

Paul's filibuster posed a challenge to the Senate more than it does Brennan or President Obama. "Is perpetual war OK with everybody?" he asked.

Brennan will be nominated anyway, but Paul's firm stance in the face of his chicken-hawk and constitutional-hypocrite colleagues is very much appreciated.

I support Rand Paul for president in 2016. It was a pleasure meeting him in person Monday evening at a fundraiser in Palatine Illinois.