According to the Constitution and precedence, federal laws are always the law of the land. States are supposed to need to prove that federal laws is unconstitut

According to the Constitution and precedence, federal laws are always the law of the land. States are supposed to need to prove that federal laws is unconstitutional, and they then wouldn’t be required to follow a federal law. Of course, a state could simply not enforce a federal law, but this is where the federal government can intervene. In the case of Washington, he used the army to enforce taxes on whiskey in Pennsylvania. Of course, he may not have been the biggest fan of using military force for policing, as he also established the US Marshals, but he was willing to use military force. Regarding states ignoring federal laws, the first I know of resulted in New York v. United States in 1992 where the Court ruled that congress couldn’t require states to enact waste disposal regulations. In more recent history, Oklahoma voted to nullify the Affordable Care Act in 2013. The biggest shift, however, was in marijuana legalization across the country. According to the federal government, pot is illegal. States have explicitly made laws stating the opposite. I can find nothing else quite like it in US history. This is different from previous cases where the states challenged a law on legal grounds. Here, they just ignored the federal government entirely.