On trade,President Donald Trump has launched lots of investigations,withdrawn from one deal and started the renegotiation of another.But this week is the first time he has put up a big new barrier On January 22nd he approved broad and punitive duties,of up to 30%on imports of solar panels and up to 50%on imports of washing machines.His backers say that the measure,which affects aroundS 10bn of imports,will protect American workers.His critics cling to the hope that the damage will be mild.Both are wrong.Start with the claims made by the administration.Workers are also consumers,and Mr Trump's actions will whack them.Tariffs raise prices and dull competition.Whirlpool Corporation,the washing machine maker which asked for the duties,knows as much.When,n 2006,it merged with maytag,arival,it quelled concerns about its high market share by pointing to competition from abroad.One study found that clothes-dryer prices rose by 14%after the merger.For washing machines,where import competition was fiercer,prices were unchanged The solar industry is a clearer case.It has about 260,000 workers,a mere 2,000 of whom were making solar cells and panels at the end of 2016.The government reckons that the fastest-growing occupation over the next ten years will be that of solar installer.The Solar Energy Industries Association,a body that is enraged by the new tariffs,reckons that the industry will support up to 23,000 fewer jobs because of them.Meanwhile,as if to underline the irony,the two companies that asked for protection are unlikely to be saved And do not forget that the tariffs may harm American industry more broadly.Restricting markets for imports tends to spark retaliation that restricts markets for exports-especially when,as with these latest tariffs,they affect everyone.China,supposedly the focus of American ire,produces 60%of the world,solar cells and is responsible for 21%of America's imports.But South Korea will also be hit,and its government is poised to dispute America's action at the World Trade Organisation.Other casualties include Mexico,Canada and the European Union That Mr Trump has stayed within the rules is small comfort:they give him enormous scope to poison world trade.And it would be wrong to skate over the differences between his administration and its predecessors.The last time this particular safeguard was applied was in 2002.It is especially belligerent.Past presidents remained wary of hurting American consumers,and mindful of international repercussions.Mr.Trump,by contrast,seems to hold a steadfast belief that protectionism works.His rhetoric-and now his actions-invite aggrieved petitioners to apply for help.The logic of his stance on trade is to use tariffs not sparingly,but repeatedly and aggressively.Mr Trump is now open for business,just not the healthy sort<br/> According to the last paragraph,to which of the following would the author most probably agree?