Those tariffs are not going to last long, the last time it was less than a year and a half or so under Bush in 2002. Could be we'll find out shortly that Canada and Mexico will be exempted if and when the NAFTA is renegotiated. And if the other affected countries agree to stop accepting heavily subsidized Chinese steel into their countries. But too many other jobs could be lost if these tariffs are allowed to continue for very long. Consider what happened when Bush imposed his tariffs on steel:
“Every U.S. state experienced employment losses from higher steel costs,” a 2003 analysis prepared for the nonprofit Consuming Industries Trade Action Coalition Foundation determined. In total, it estimated that 200,000 American jobs — a larger number than the entire steel industry employed at the time — were lost as a result."
AND:
" But even if tariffs save every one of the 140,000 or so steel jobs in America, it puts at risk five million manufacturing and related jobs in industries that use steel. These producers now have to compete in hyper-competitive international markets using steel that is 20 percent above the world price and aluminum that is 7 percent to 10 percent above the price paid by our foreign rivals.
In other words, steel and aluminum may win in the short term, but the‎ steel and aluminum users and consumers lose. In fact, tariff hikes are really tax hikes. Some of those five million jobs will be put in harm’s way. If they sell less to foreigners, the trade deficit goes up, not down. Since so many of the things Americans consumers buy today are made of steel or aluminum, a 25 percent tariff may get passed on to consumers at the cash register. This is a regressive tax on low income families. "
I think the risk of lost jobs is not as high as some suggest, but the negative aspects are not as insignificant as others say either. However, this may be a case of Trump's negotiating tactics to get better trade deals.