Theodore Postol, a technology and national security policy professor at the Massachusetts Institute of Technology, said any response to the growing North Korean nuclear expertise has both political and technical complications. He favors a technical response: As North Korea continues to advance its long-range missile program through launches, stop those launches from being productive.

“This could be done by shooting down North Korean . . . launches while the rockets are in powered flight,” he wrote in an email Tuesday, referring to the moments after launch when a missile is still in its “boost phase” – gaining speed as its engines labor against the Earth’s gravity to boost the rocket into space.

Such a tactic would be particularly effective against North Korea’s Unha-3, Postol argues, because it is a relatively slow rocket.

He said the United States or the United Nations could cite the right of self-defense as a justification for such a shoot down, which would “ensure that North Korea’s long-range rocket program could be stopped in its tracks.”

Postol adds that any legitimate satellite launch would differ from the test of an intercontinental ballistic missile in several easily observed ways, from trajectory to weight to the ships at sea to monitor the flights. Any test showing the signs of an ICBM test “would certainly justify military action to stop the program from moving forward.”

He noted that his idea is less aggressive than the most likely alternative, attacking the rockets on North Korean soil. And, he said, while this would be a new system, he believes current U.S. technology makes such interceptions possible, and North Korean technology makes it unlikely they would develop rockets fast enough to overcome such a strategy for, perhaps, decades.

Decades is likely to be important. Ellen Kim, a Korea expert at the Center for Strategic and International Studies in Washington, said that it is highly unlikely North Korea will retreat.

“North Korea isn’t going to give up its weapons program, no one ever does,” she said. “North Korea sees advancing its nuclear program as a way to increase its bargaining power.”

In reality, it’s often worked the other way, with the international community seeing the program as a reason to cease negotiations. And, while negotiations are ceased, North Korea advances its nuclear program.

“We will go back to diplomacy, eventually,” she said. “But we will have lost a lot of ground before that.”