If you do not protect income how are you protecting people?

Donald Trump has promised a 35% tax on cars and parts produced by Ford in Mexico and a 45% tax on imports from China, inviting criticism from economists. So, is protectionism necessarily a bad thing asks Professor Eichengreen from the US. If the US imposes taxes on imports from other countries they will retaliate by imposing taxes on US goods and global trade will suffer as investment collapses. Apparently, the Great Depression was exacerbated by the Smoot-Hawley Tariff in 1930. But that reasoning may not apply to the present slowdown in global growth. " When the economy is in a liquidity trap - when demand is deficient, prices are stagnant or falling and interest rates approach zero - normal macroeconomic logic goes out the window," writes the professor. If President Trump imposes taxes on goods from China and President Xi retaliates by imposing taxes on goods from the US trade should fall and both countries should suffer. " But when deflation looms, upward pressure on prices is just what the doctor ordered. Higher prices encourage firms to raise production and households to increase their spending. They also reduce the burden of debts. And because inflation is still too low, owing to depressed macroeconomic conditions, there is no need for the Fed to raise interest rates and offset any inflationary effects of the increase in spending." Free trade is not necessarily good for developing countries. China and Vietnam developed by imposing business subsidies, domestic-content requirements, investment regulations and import barriers, while Mexico has languished by relying on free trade alone. Japan, South Korea, Taiwan and China had phenomenal export-led growth when import tariffs in the US and Europe were higher than they are today. Free trade deals may not be necessary. People in rich countries see free trade as the cause of rising unemployment and falling living standards. This is what binds Donald Trump and Brexit. People, who were solid Democrats in Pittsburgh, are going to vote for Trump. Why? " We've lost people here," said Del Signore." Why did we lose people? Because we lost the coal, the coal mining jobs. We lost the steel mill jobs. We lost the railroad jobs. Because they went overseas, or somewhere else, and we've suffered. It's a shame. But that's what happened. We're the Rust Belt." Why is there a liquidity trap when central banks in the US, Europe and Japan have poured trillions of dollars into their economies by buying up bonds, also known as Quantitative Easing? At the same time interest rates are close to zero in the US and negative in the Eurozone and 4 other countries. Nations protect their borders, what is wrong in protecting their economies? Only if they can stand up against business lobbies. Need guts.