Tariffs don't hurt the producer as much as the consumer. But stupid politicians will tell you otherwise because they think they are smart!
Can you explain this a bit more? If there's a tariff on a component, wouldn't the buyer look for cheaper domestic replacements? So maybe a mix of both -- they pay more in the short term, but it gives domestic suppliers a better chance to win the business over the long term?
The key thing is whether the product is fungible.
A Boeing part isn't going to be useful to repair an Airbus owned by a US carrier.