United States President Donald Trump has vehemently insisted that he is “not backing down” on his plan to putt heavy tariffs imported steel and aluminium. This has received a mixed reception from democrat and republicans alike. House Speaker Paul Ryan has voiced opposition to this as well as a number of other congressional republicans claiming it may spark a trade war. We spoke to Professor John Romalis, a Professor in Economics at Sydney University who specializes in International Trade and International Macroeconomics.