Congratulations are in order in respect of Senator Lee of Utah, who is now calling for bringing back into use the little discussed constitutional war power known as the letter of marque and reprisal. These letters, granted by Congress, are in effect licenses for private individuals to conduct war on behalf of the United States. It’s Senator Lee’s idea that they are a perfect instrument to deploy in this era of drug cartels and asymmetrical warfare.

We agree. The Sun has been one of the few, if not the only, newspaper to endorse the use of letters of marque and reprisal. They are the second war power granted to congress in Article I, Section 8, of the Constitution. That section grants Congress such powers as to declare war, raise an army, provide and maintain a navy, and “grant letters of marque and reprisal.” We granted letters of marque against the Barbary Pirates, back in the day. 

In the 19th century, though, letters of marque and reprisal began to go by the boards. A number of major countries in Europe went so far as to outlaw — by treaty — the use of letters of marque and reprisal. America, though, had the good sense to refuse to ratify the treaty, and letters of marque and reprisal are still legal. Just weeks after 9/11, Congressman Ron Paul proposed that America issue letters of marque and reprisal against Osama bin Laden.

Dr. Paul’s bill, which we endorsed, would have provided up to $40 billion in rewards for any holder of a letter of marque who brought back bin Laden dead or alive. Dr. Paul, who has a libertarian streak, thought it would be a better way to go after bin Laden than by spending trillions and sending an army overseas. It was Dr. Paul’s thinking that granting letters of marque would be a less expensive and more efficient way of defeating bin Laden.

Dr. Paul, as we put it in these columns at the time, unsheathed the constitutional sword within days of Al Qaeda’s attacks on New York and Washington. His bill was the September 11 Marque and Reprisal Act of 2001 to authorize private parties to go after Osama bin Laden. He has pressed continually since then for legislation authorizing the granting of such letters, delivering an eloquent exposition to anyone who will listen.

Glenn Reynolds, in a column we read in the New York Post, has a good description of how letters of marque work. “In old-fashioned naval warfare, a government letter of marque allowed a privately funded and operated warship to set sail and seize enemy ships, typically in international waters,” he writes. “Once vanquished, an enemy ship and its cargo would be taken to a friendly port and adjudicated as legitimate (or not) by a prize court.”

Mr. Reynolds, a law professor, writes in the Post that “legitimate prizes could be sold, and the privateer got to keep the money.” The tactic, he suggests, could be deployed against maritime targets like Iranian oil tankers. It’s Senator Lee’s idea that letters of marque could be used against, say, the cartels. We write just to mark our long-held view that this constitutional feature once deemed obsolete may find a new relevance in today’s world.

Mr. Lee’s proposal to bring back letters of marque sparked, Mr. Reynolds writes, “a flood of skull-and-crossbones memes and ‘avast, me hearties’ responses” but also some serious ones. Turns out there are features in the Constitution that have rarely been used but suddenly look relevant or even inspired. In a time when America shrinks from a draft, a grant by Congress of letters of marque could unleash a new burst of patriotism in a time when we need it.