Government command and control of the economy
Donald Trump has implemented policies that have been very good generally, but the one area where he fails consistently is on free trade. Part of the reason for that is spineless Republicans have abandoned their long-held conservative principles to bow to Trump (as I predicted would happen in 2016), but also because conservatives have not used the best arguments to fight against increased tariffs - or as I like to call them, import taxes.
The issue is not the nebulous concept of free trade. The issue is the fact that tariffs (import taxes) are a burden on the American people and restrict our liberty to buy the products we want. Import taxes punish the American consumer economically for not making the "right" decision about what products to buy. The economic harm on consumers then benefits domestic industries, who see more sales as foreign products are priced out of reach.
Trump likes to talk about how our trading partners are taking advantage of us, but the real "enemy" is the American people making hundreds of millions of economic decisions each day. American consumers have chosen to buy certain products made outside our borders and domestic businesses have not offered a better product at a better price to lure those consumers back. So instead of competing and winning (or reducing regulatory burdens that get in the way of competing and winning) protectionists want to punish the American people by making them pay higher import taxes.
This is not conservatism. This is top-down central planning by politicians seeking political support from industries they protect. This is the government telling you that they know better how to run your household than you do. Worst of all, this is a betrayal of our system of constitutional checks and balances. The reason Trump is able to unilaterally raise import taxes is because Congress gave that authority to the executive branch decades ago. It is long past time for Congress to take that authority back and put it where it belongs.