When the United States began sinking boats on suspicion of drug trafficking – with no warning, no arrests and no evidence recovered – we crossed a line. These so-called narco-terrorist strikes may be politically popular, but they are legally indefensible.

Now, reports indicate that the British government has stopped sharing intelligence with Washington, DC, over fears that the U.S. operations violate international law. If true, one of America’s oldest allies is signaling what many of us who served in uniform already know: Justice and lasting security cannot be achieved through lawlessness.

For more than two decades, the U.S. Coast Guard’s HITRON program has proved that there’s a better way. Helicopter-based marksmen disable engines on fleeing drug boats, allowing suspects to be arrested, evidence recovered and intelligence exploited.

More than 1,000 vessels have been stopped this way, without deliberate loss of life. It is effective, lawful and consistent with both our national values and our obligations under the law of the sea.

The only flaw is that we have not assigned enough ships and aircraft to this effort. This new approach – destroying boats outright and killing the occupants – abandons that model and the principles behind it. In addition, it sets a frightening example for other nations throughout the world.

In any legitimate military or law enforcement operation, rules of engagement exist to ensure that force is necessary, proportionate and discriminate. These rules are designed to protect innocent life, preserve evidence and maintain compliance with the Law of Armed Conflict – the body of international law that governs when and how force may be used.

The supposed justification, that these boats pose a “clear and present danger” to Americans, falls apart under scrutiny.

The 

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