Tariffs don't hurt the producer as much as the consumer. But stupid politicians will tell you otherwise because they think they are smart!
Besides, there are big strategic reasons to maintain a strong domestic aerospace industry, even if it increases costs in the short run.
Also, aggregate wealth of a nation isn’t the only thing we should be targeting. You can increase the overall wealth while simultaneously demolishing the wealth of the large portion of your populace involved in domestic manufacturing.
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.