What worked in the past may not work in the present, and tactics to rein in one country could prove disastrous if pursued with others.
For Bennett Ramberg's latest contributions to The Japan Times, see below:
The belief we can make nuclear North Korea go away is a mirage.
More efforts are needed to develop well-considered and broadly supported plans to secure nuclear weapons in volatile regions.
Nuclear reactors are likely terrorist targets and not enough is being done to protect them.
It is inconceivable that Kim Jong Un would give up the weapon that places his nation in the exclusive nuclear club, and sanctions won't force him to do so.
Regardless of whether the North Korean regime collapses with a bang or a whimper, ensuring that the country's nuclear weapons are not used, moved or exported is a task that will require the capabilities of the U.S. armed forces.
The inherent danger in possessing nuclear assets becomes far more acute in a combat zone, such as today's Middle East, where nuclear materials and weapons are at risk of theft, and reactors can become bombing targets.
Twenty-eight years after its Chernobyl nuclear plant exploded, Ukraine confronts a nuclear specter of a different kind: the possibility that the country's reactors could become military targets in the event of a Russian invasion.
There are many obstacles to an agreement on Iran's nuclear program. Particularly troubling for the U.S. and its allies, though, is how much Iran has mimicked the regime in Pyongyang.
Syria's chemical-weapons stockpile is dangerous, but so are the remnants of a North Korean-engineered nuclear reactor buried beneath a base overrun by Syrian rebels.