The U.S. House of Representatives approved tough legislation on May 4 to increase sanctions against North Korea by cutting off the recalcitrant regime’s sources of cash. The bipartisan bill includes wide-ranging measures to block crude oil exports to the North (which are, in fact, the regime’s economic lifeline), to prohibit the use of any slave labor that North Korea exports to other countries, and to ban online commercial activities with the country. The legislation is much tougher than the North Korea Sanctions and Policy Enhancement Act of 2016 and the United Nations Security Council resolutions, which indicates that Congress is taking the North’s nuclear and missile provocations seriously.

It is worth noting that China is actively engaging with the U.S. to put pressure on Pyongyang. Beijing, which has recently expressed doubts through its state news media about the validity of the Sino-North Korean Mutual Aid and Cooperation Friendship Treaty, reportedly instructed its financial institutions to not conduct any transactions with the North. It appears the cooperation between the U.S. and China in dealing with the rogue regime began in earnest after the April 6 U.S.-China presidential summit. Seoul, too, has responded to the North’s nuclear and missile provocations in cooperation with Washington; in this context, it approved the deployment of a missile defense system on the Korean Peninsula, known as the Terminal High Altitude Area Defense system, sparking fierce controversy.

Given that situation, the posture of the new South Korean administration, which will take office on May 10, might pose a problem. Exploiting President Donald Trump’s statement that he wants the South to pay for the missile defense system, some presidential candidates mentioned the need for parliamentary ratification of the THAAD deployment, with a hint that they may overturn the installation decision, making South Korean citizens uneasy. However, the task at hand is to enforce the original arrangement between the two allies to share the cost of deployment, not to start from square one and reconsider whether to install the missile defense system.

If the new government attempts to disregard the U.S.-South Korea alliance and push for a different approach, it is highly likely that “Korea passing” – the idea that Washington and Beijing will handle the North Korea problem without consulting the South – will become a reality. Two international strongmen, President Trump and Chinese President Xi, have so far made numerous comments that focus on putting their national interests first in all areas, including security and trade. If the South disengages from trilateral cooperation with the U.S. and China in pressuring the North because of the circumstances of the two nations’ foreign policy platforms, the prevention of “Korea passing” might not be guaranteed and, in turn, a serious threat will be posed to South Korea’s security. Therefore, the next administration should actively engage in the long-awaited trilateral cooperation to rein in the reclusive regime’s nuclear provocations, as it is the only way to resolve the North Korea problem and maintain national security.