But to your question. Why should the American taxpayers foot the bill for trade with Castro, giving tacit approval to his regime
and freeing up his ill gotten gains (90% of all wages) to sponsor international terrorism?
Trade is a two way street and is also a fundamental right of being alive. The Congress doesn't have the right to prohibit trade and I defy you to find that power listed anywhere in Article 1 Section 8 where their power is defined.
There is no taxpayer cost to trading with Cuba other than the goods and services that they might purchase.
If the rationale that is posited about trade with China is correct (that it actually helps bring China into relations with the world and in effect "corrupts" their communist ideals) then the same can be said for Cuba. Turning a communist nation into a capitalist nation is bad why?