Carbon frame manufacturing is far more capital intensive than most metal bike manufacturing. Also, the economies of scale in carbon manufacturing are very powerful. The supply chain and necessary scale for high end carbon frame manufacturing is all in Asia these days (primarily Taiwan). In addition, the skilled labor and engineering prowess is also all in Asia these days. American carbon frames would either be lower quality or vastly more expensive than comparable Asian frames.

Speaking of "stealth" (and to get political here), tariffs are nothing more than a politically palatable way to support US companies by levying a tax on American consumers. We the consumers are ALWAYS losers with tariffs. Politicians like to pretend it's a free lunch. Tariffs are almost always value destructive and inefficient. If you want to help American companies, it would be more efficient to just give them money, like the Chinese do.