Here’s an example of the 10th Amendment in action:
While the United States and Iran edge closer to a nuclear deal, nearly two dozen US states are imposing their own sanctions against Tehran—a move some say could derail fragile talks between the two countries.
The states, though, say they aren’t budging. In fact, Kansas and Mississippi are even considering adding more sanctions.
And
Several states across the country have put their own measures in place to punish Iran-linked companies operating in certain sectors of its economy, directing public pension funds with billions of dollars in assets to divesting from the firms and sometimes barring them from public contracts[.]
Other states doing this sort of thing include Connecticut, Florida, Georgia, Illinois, Michigan, New York, and Oregon, among others.
Would that the White House had similarly capable judgment.