Tariffs are tricky because they create price distortions in the market. Prices should ideally reflect only people’s production and consumption preferences. Anything exogenous to that supply/demand dynamic will distort prices, and mess with the coordinating function of a free market.
Also, tariffs tend to generate retaliatory tariffs. And the last time we had a full-blown tariff war, we got a depression, FDR, and the New Deal, which we have been paying for ever since....
As for a taxation system, the income tax has to go. And forget about a VAT! I’m open to either a fair tax or a consumption tax, but I honestly haven’t studied either one enough to make an informed decision yet.
US companies shutting down their US factories and idling 100's if not thousands of workers so they can exploit virtual slave labor and re import back duty free into the USA is causing real distortions too. To make matters worse for domestic competitiveness there is a "duty" on US labor in the form of income taxes.