Europe does not understand the logic of proposed US steel tariffs on the basis of national security concerns, European Commission First Vice President Frans Timmermans said on Monday, according to Reuters. US President Donald Trump had pressed ahead with import tariffs of 25 percent on steel and 10 percent for aluminum, declaring metals production to be a matter of national security. “If he says the reason for these measures is security, then we say there is no reason to impose these tariffs on us. How is European steel a threat to the US,” Timmermans said at a steel conference held in Dillingen, Germany. Timmermans added that “if it becomes necessary, we will prepare countermeasures, but these will conform to World Trade Organization rules.”