In practice, laws that constrain the national-security state are easily circumvented. All that's needed are creative lawyers and arrogant officials. Here's how the Colombia operation got approved, according to the Post:

White House lawyers, along with their colleagues from the CIA and the departments of Justice, Defense and State, had their own questions to work through. It was one thing to use a PGM to defeat an enemy on the battlefield—the U.S. Air Force had been doing that for years. It was another to use it to target an individual FARC leader. Would that constitute an assassination, which is prohibited by U.S. law? And, “could we be accused of engaging in an assassination, even if it is not ourselves doing it?” said one lawyer involved. The White House’s Office of Legal Counsel and others finally decided that the same legal analysis they had applied to al-Qaeda could be applied to the FARC. Killing a FARC leader would not be an assassination because the organization posed an ongoing threat to Colombia. Also, none of the FARC commanders could be expected to surrender. And, as a drug-trafficking organization, the FARC’s status as a threat to U.S. national security had been settled years earlier with Reagan’s counternarcotics finding. At the time, the crack cocaine epidemic was at its height, and the government decided that organizations that brought drugs to America’s streets were a threat to national security.

When I read sentences in the newspaper like, "Killing a FARC leader would not be an assassination because the organization posed an ongoing threat to Colombia," I mourn for a world where newspapers are so accustomed to dubious logic from national-security officials that the leaps are no longer even remarked upon.

Almost every link in that chain of reasoning is problematic, but none is particularly surprising. Civil libertarians have been fighting to constrain the national-security state in the War on Terrorism in part because once a line of reasoning is used to empower the government to fight one thing, the power is invariably used elsewhere. First, national security supposedly demands that the president be allowed to order due-process-free assassinations of suspected terrorists. Not so long after, national-security officials are using the same precedent to help kill FARC in Columbia.

Where does it end?

Here's another example of War on Terror logic spreading from one conflict to another:

Just across the Putumayo River, one mile inside Ecuador, U.S. intelligence and a Colombian informant confirmed the hideout of Luis Edgar Devia Silva, also known as Raul Reyes and considered to be the No. 2 in the seven-member FARC secretariat. It was an awkward discovery for Colombia and the United States. To conduct an airstrike meant a Colombian pilot flying a Colombian plane would hit the camp using a U.S.-made bomb with a CIA-controlled brain ... U.S. national security lawyers viewed the operation as an act of self-defense. In the wake of 9/11, they had come up with a new interpretation of the permissible use of force against non-state actors like al-Qaeda and the FARC. It went like this: If a terrorist group operated from a country that was unable or unwilling to stop it, then the country under attack — in this case, Colombia—had the right to defend itself with force, even if that meant crossing into another sovereign country.

Take every prerogative that George W. Bush claimed for the United States after 9/11 and imagine extending it to Colombia too. Yes, America really is that shortsighted.