Sen. Paul’s drone filibuster last year made him the go-to presumptive candidate for civil liberties-emphasizing Republicans. The smart thing about that filibuster was that he wasn’t asking for the impossible; he sought a small, but significant disclosure from President Obama that he did not have the authority to drone-kill an American citizen in the United States.

This week, Sen. Paul continues that smart strategy:

Paul, the junior Republican senator from Kentucky, has informed Reid he will object to David Barron’s nomination to the 1st Circuit Court of Appeals unless the Justice Department makes public the memos he authored justifying the killing of an American citizen in Yemen.

The American Civil Liberties Union supports Paul’s objection, giving some Democratic lawmakers extra incentive to support a delay to Barron’s nomination, which could come to the floor in the next two weeks.

Barron, formerly a lawyer in the Justice Department’s Office of Legal Counsel, penned at least one secret legal memo approving the Sept. 2011 drone strike that killed Anwar al-Awlaki, a radical Muslim cleric whom intelligence officials accused of planning terrorist attacks against the United States.

The attack also killed another American citizen, Samir Khan, the creator of an online magazine catering to jihadists.

Put simply: no memo, no vote.

It is not an outrageous ask for Paul considering that the Second Circuit has already ordered Justice to release portions of the memos at issue. The court’s reasoning is noteworthy, by the way: “a unanimous three-judge panel said the government waived its right to secrecy by making repeated public statements justifying targeted killings.” In other words, if Obama wants to brag about drone killing, he’s going to have to explain himself when asked for legal justification.

Paul is walking a fine line in the run up to 2016.  He’s strong on drone killing, but weak on Iran. He endorsed Sen. Collins on the one hand, but on the other campaigns for Greg Brannon. The big thing Paul has going for him is that, much like his father, he seems to motivate supporters who would otherwise throw up their hands and walk away.