Editor's note: Tom Fowdy, who graduated from Oxford University's China Studies Program and majored in politics at Durham University, writes about international relations focusing on China and the Democratic People's Republic of Korea. The article reflects the author's views, and not necessarily those of CGTN.

Since the dramatic ending of the summit between the two leaders in Hanoi, some voices in Washington have continued to call for increasing sanctions on the DPRK. Yesterday,  the U.S. national security advisor John Bolton called upon China “to do more” in assisting the denuclearisation of the DPRK, demanding Beijing place additional pressure on Pyongyang to facilitate more favorable results for Washington.‍

In addition, two United States senators, Cory Gardner (Colorado) and Ed Markey (Massachusetts) sent a letter to the White House questioning why the administration has been lenient on what they termed “the doctrine of maximum pressure” and new unilateral sanctions designations from the Treasury Department. The call for more measures on DPRK comes as America's position as a whole on Pyongyang becomes more impatient and uncompromising.

But what will even more sanctions on the country achieve? Not a great deal. The DPRK's increasingly sophisticated methods of sanctions evasion, combined with weariness from the international community against U.S. unilateral designations don't offer much scope.

In addition, Pyongyang will almost certainly see such an approach from Washington as a frontal effort in forcing the country's unilateral capitulation, which will only heighten the probability that the country will return to missile testing to strengthen its own hand against the White House. In essence, in this given scenario more sanctions will lead nowhere, rather than strengthening diplomacy.

The United States has an enormous range of unilateral designations in place against the DPRK. Using the power of the dollar and its necessity to international finance, fuel, and commerce, U.S. policymakers have long argued that designations by the department of the treasury can create de-facto deterrence against adversarial states by doing serious businesses, banks and enterprises avoid the given target. 

These measures have been enabled through an ever increasing number of congressional acts which have offered the Presidency the executive power to blacklist perceived violators. The list of designations grew rapidly throughout 2017 and early 2018, the administration has decided to stop following the Singapore summit seeking to facilitate diplomacy.

To resume sanctions would not come with guaranteed effectiveness. First of all, DPRK's ability to avoid them is often underestimated. A recent report by the United Nations Panel of Experts in March found that Pyongyang had utilized increasingly shrewd methods to find ways around existing United Nations, and thus U.S. unilateral designations, and continue to minimize the damage of the measures by a variety of means. 

Maximizing unilateral sanctions would not substantially change this. While undoubtedly it may deter bigger businesses from associating with DPRK, the measures are at best a form of extra-territorial jurisdiction, which unless they are in the scope of UN boundaries, cannot be easily enforced abroad. This makes many U.S. designations largely symbolic at best with bigger scope available for them to be dismissed or avoided.

For example, lots of ships designated only by Washington over DPRK related activities continue to operate regardless. Pyongyang also continues to find backdoors to the international financial system.

Secondly, an increase in unilateral designations by Washington is only likely to change Pyongyang's behavior in counterproductive ways. Following the aftermath of Hanoi, DPRK diplomats have been increasingly vocal against what they see as Washington seemingly demanding a unilateral capitulation from the country towards denuclearisation, than mutually beneficial talks.

As a result, the country's vice foreign minister relayed a threat to resume missile testing if Washington was not prepared to take negotiations fairly. The country has already made its offer of concessions and is now refusing to budge. Increased efforts at sanctions by the U.S. Treasury Department will only vindicate the view that the White House is not acting in good faith, which would increase the probability of them eventually responding in order to procure their own leverage.

Ultimately, they will feel they have no choice but to return to missile testing in order to maintain a balance in negotiations, something which will in fact further undermine denuclearisation efforts and harm regional security.

Thirdly, the United States risk spreading themselves too thin. Since the demise of the crisis of 2017, Trump's foreign policy priorities have shifted in placing large scale designations and thus pressure, on other countries such as Iran and Venezuela. In doing so, the Treasury's work on the DPRK was minimized to incorporate this shift.

To make more unilateral designations means stretching the department's resources and actively juggling three countries as priority cases at once. Bare it in mind, to make designations requires extensive research and examination of a company's transactions, thus a need to require very specific intelligence.

How do you prove, for example, a bank has ties to Pyongyang? The practical side of this work is important, which makes chasing several countries at once a huge challenge.

In summary, although some voices are calling for more pressure, placing more unilateral U.S. designations on the DPRK will not only fail to yield positive or productive results but will risk undermining diplomacy as a whole on the Korean Peninsula. U.S. sanctions are powerful, but in the current situation with Pyongyang, they have been overused and now only offer limited effectiveness.

Yet, they will be provocative enough in order to make Kim Jong Un feel that continued missile development is a necessary response in avoiding unilateral capitulation and holding his own in talks. In this case, more measures can only serve to undo all progress which has been made so far.

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