We can not be the policeman of the world, we can not protect countries all over the world, where they're not paying us what we need. When asked whether United States has to do something regarding North Korea, National Security Adviser H.R. McMaster said, Well yes, we do have to do something, and so we have to do something, again, with partners in the region and globally, and that involves enforcement of the UN sanctions that are in place. United States may mean ratcheting up those sanctions even further, and it also means being prepared for military operations if necessary, he said. Trump has, since in office, attempted to form alliances with world leaders to solve such global crises as the Syrian civil war and the North Korea nuclear threat, including an outreach to China President XI Jinping.