Trump did campaign on Law and Order, but also said many times that marijuana laws should be up to the states.
That said, you are 100% correct that Congress needs to act. 29 states and DC have legalized marijuana for medical use and a handful have also legalized for recreational use. It’s time that Congress adjusted the laws to give these states the right to do so. Right now, they are just thumbing their nose at federal law and the DOJ has (up until now) been told to lay off enforcement.
The problem with this is that giving the states back their rights requires Congress to do something and what’s the likelihood of that?
Obama set the precedent for what pot does to ones brain. Stuck on stupid!