This article was originally published on CNBC.com.
Since Trump took office just short of one year ago, his administration has significantly expanded both United Nations Security Council and U.S. sanctions against North Korea. Even so, North Korea's 25th missile test of 2017 on November 28 is the latest indication that expanded sanctions have yet to achieve their goals.
Some might argue that sanctions need more time or even that we need to move beyond sanctions to resolve the growing threat of North Korea's nuclear weapons and missile programs.
Expanded sanctions now under consideration include a more assertive interdiction and inspection authority from the UN, similar to those imposed against Iraq in 1990. Not surprisingly, North Korea has responded defiantly, suggesting that would constitute a naval blockade and an act of war.
However, before we go traipsing onto the battle ground, the Trump Administration would be well advised to take a crash course in the art of sanctions.
For sanctions to work, the state imposing the sanctions and the state being sanctioned have to understand why sanctions are being imposed and how sanctions can be relieved. Using sanctions properly is not just about how many can be imposed or how many targets can be designated; it is also about the underlying strategy and objectives being pursued.
While the exact details and the physical pressure created by sanctions are also important, both are less so than the principles behind the decision to sanction and what it would take for them to end.
In the case of North Korea, we presently lack any real sense of the purpose behind the sanctions imposed by the Trump Administration and their desired end state.
We know that the Trump Administration – like others before it – considers North Korean nuclear weapons unacceptable and has said that it must eliminate them and stop testing missiles. If not, Trump has said "additional major sanctions" will be imposed.
But, does that mean North Korea would have to abandon all nuclear activities or just bombs? Would North Korea have to abandon all missiles or just some? Answers to these questions are important, not least because without them, we don't know if we are chasing an objective that may prove impossible or if our sanctions are remotely in line with our demands.
From the North Korean side, we have clear statements of intent. Because their rhetoric is intended to signal continued North Korean resolve in the face of sanctions--in addition to undermining the international coalition imposing sanctions on the country--it is hard to tell how far to take its statements. But, North Korea is making it clear that it has no intention of backing down.
On November 17, North Korea's Ambassador to the United Nations in Geneva underscored in an interview with Reuters that North Korea's nuclear weapons are not on the table for negotiations, citing the need for "the nuclear deterrent to cope with the nuclear threat from America."
Worse, though Han also dismissed the idea of a "freeze for freeze" or trading the nuclear and missile program for sanctions relief, Han stated that, "It is obvious that the aim of the sanctions is to overthrow the system of my country by isolating and stifling it and to intentionally bring about humanitarian disaster instead of preventing weapons development as claimed by the U.S. and its followers."
This comment underscores that North Korea's government perceives a different intent behind U.S. and UN sanctions against the country than that of dealing its weapons programs and human rights violations.
This is a big problem, but not insurmountable. Communication and clarity of purpose are key.
As one of the lead architects of the U.S. and international sanctions regime against Iran, as well as a negotiator for the resulting nuclear deal, I think the history of sanctions with Iran is instructive for U.S. policy toward North Korea.
Despite a decade of increasingly tough sanctions, the United States was unable to secure Iran's agreement to take the kinds of steps necessary to permanently resolve concerns with its nuclear program.
The agreement reached in July 2015 instead intended to resolve those concerns for an extended period of time, permitting both greater confidence to be built by Iran as to its intentions and a foundation to be built for perhaps a longer term solution to the problem in the future.
The jury is still out as to whether the agreement will survive long enough for these propositions to be tested. But, it was built on a framework of clear communication from the United States.
Its objectives were to address concerns about Iran's nuclear program, and to receive communication and assurance from Iran as to its willingness to resolve those concerns, along with its limits in doing so. From this, we obtained restrictions on Iran's nuclear program and transparency into it, but with sunsets attached to many of these provisions that will lapse in 10-20 years.
If sanctions continue to be the policy tool of choice, then Trump and his team must commit to open dialogue with North Koreans to explore what may be possible. Sanctions do not work without being attached to a political and diplomatic strategy.
Secretary of State Tillerson has implied that there are ongoing, back channel talks with and about North Korea. Hopefully, in those talks, there is greater clarity being offered about why sanctions are being pursued and what the United States would expect and demand to begin their removal. Absent that, sanctions lose much of their diplomatic value.
They may still deprive North Korea of resources and freedom of action, which has its own utility. But, part of the art of sanctions is their contribution to long term political solutions, for which clarity and communication are key.
Commentary by Richard Nephew, a senior research scholar at Columbia University's Center on Global Energy Policy and the author of the new book, The Art of Sanctions: A View From the Field, by Columbia University Press. He was the former principal deputy coordinator for sanctions policy at the Department of State and former lead sanctions expert for the U.S. team negotiating with Iran. Follow him on Twitter @RichardMNephew.