The Trump White House intends to step up the war on drugs including certain substances that individual states have made legal for recreational use (marijuana).
Bearing in mind that Nixon, who signed the original Controlled Substances Act and created the DEA, is suspected of instructing law enforcement to use the law as an excuse to arrest protesters (while the United States has protections for free speech, any protester with so much as a gram of marijuana on him could be arrested and held in jail; meanwhile, as felons, they lose the ability to vote), it is possible Trump could use the very same laws to arrest and disenfranchise liberal citizens who would oppose him both in embarrassing protests and future elections.
If Trump were to attempt this, I wonder what positions the states would take? Specifically, those states that have legalized it. I don't expect anyone to answer that (it would just be speculation).
But I think a legitimate and relevant question is-- how did the states handle it during the Nixon administration? Were they complicit with federal efforts to arrest war protesters on the grounds of drug possession? Or did they attempt to protect their states' citizens' rights? What insight does this give us into what states would and could do today?