The Commerce Clause and Twisted Logic

"To regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes;"

This is the clause of the US Constitution which the Federal Government uses to justify just about everything it does in respect to the economy; saying it gives them the authority to make laws about everything that affects commerce among the states. Such laws include gun laws, EPA restrictions, and agriculture laws; just to name a few. They contend this clause gives them the power to regulate even things which stay within a certain state if anything used for that product comes from out of state (i.e. a screw or paint).

However, by that logic, then the Federal Government would have the power to extend these types of laws to foreign Nations. Seeing as they do not have that power and never did or will, how can different logic be applied to a another clause of the same sentence?

The Supreme Court has 40 some case decisions on The Commerce Clause, and I am not familiar with all of them, but I don't see how this twisted logic can stand. The Federal Government can not logically have more power to regulate commerce among the states than it does with foreign nations.

Maybe if the courts actually read the Constitution and not case law this fallacy can be reversed, but I don't hold out hope.