President Donald Trump is preparing to formally announce 25% tariffs on steel and aluminum imports. It's part of an aggressive effort to remake the existing terms of world trade that so far has compounded economic uncertainty.

Steel and aluminum are heavily used in the automotive and construction industry, but are also used to manufacture goods and appliances. The decision mirrors the actions Trump levied during his first Administration, when he enacted a 25% tariff on steel and 10% tariff on aluminum, though some countries, including South Korea were exempt.

The 25 percent tariff the president is proposing is almost identical to a move in his first term. Economists and foreign governments know what will come next.