Learn me about tariffs

Example:

I built a CNC router and needed to buy a high-speed spindle motor. I found it at a very good Chinese supplier and ordered it. The Chinese supplier warned me that some US customers have had to pay up to $$$ in tariff charges, which is between the buyer and Customs. Several weeks later it's stuck in Anchorage (or it may have been Memphis, don't remember). Customs sent me an email, wanting a bunch of forms filled out, which I did, replying to their email. After a couple more weeks, Customs said I hadn't replied, so they sent it back to China! Keep in mind that the motor is over 40 lbs, so freight was a big deal. I and the seller went back and forth about what to do, as I had all but given up getting it through Customs. They convinced me to give it one more try, this time using a different carrier. This time, it flew right through our system and I had it within a week - no nothing from Customs. Okay, so there's that, that Custom's involvement seems inconsistent. Now the rant.

I understand what tariffs are supposed to do: protect domestic sources by punishing foreign producers with additional fees on the products. The idea is that the buyer will be put off by the high price and instead locate a domestic source. Okay, got it, but here's the problem: There are NO domestic manufacturers for this type of spindle motor, none, zero. Here's a case where the supplier's price is artificially inflated by our own government, and if I want the produce, *I* have to pay the higher price, as there is no alternative. I can't help but see this as punishing not the seller, but the buyer, as my choices seemed to be to, A. Pay the tariff to get what I want, or B. Don't use that type of spindle motor. There are some others... made in Germany, so that situation is no better.

That's the problem with tariffs particularly those that are broadly enacted.

Short-term fix: order a hoard of those spindle motors right now just to be safe.

Whoever does the import paperwork has to assign a country of origin and an HS code to the goods. It is pretty much an honor system and I expect someone just wrote Taiwan or Japan or used a non duty HS code on the form the second time. Sometimes you can play with the codes to get the result you want. For example an electric motor could be an electric motor, or it could be router parts. One may be tarriffed and one may not. 

Tariffs are not really intended to "protect local businesses" -- that's just the way politicians spin it to try to convince people that they're not evil.

Tariffs are really about "rent seeking", which is where one group of people uses government force to enrich themselves at the expense of other groups of people.  Sure, there's no one who makes those spindle motors in the US (or wherever you live) today, but likely there was at one point.  Either that or the particular tariff law that was passed was written sufficiently broadly that it covered some things that the people who paid for it didn't intend to cover but didn't care enough about to get it changed before being passed.

Tariffs reduce economic efficiency and thus make both countries worse off as a whole.  They only benefit a small subset of one country and that is outweighed by the cost to the rest of that country.