State legalization of cannabis does not apply to federal property or properties under federal jurisdiction within the state.
While several more states just legalized recreational and medicinal use of cannabis, those laws apply only to areas not under federal control. Given that many of these states are in the west, where the federal government owns huge portions of the land, that means that cannabis could still be illegal in many places in those legal states.
Nevada is the most dramatic example. With 84.5% of its land mass under federal ownership and/or control, state legalization applies only to a small portion of Nevada. And with no clear boundaries visible to travelers you could easily find yourself in illegal territory carrying a purchase home from a dispensary. In fact, you might cross in and out of these areas several times, given the great expanse of that state and the distances between towns and cities.
And here is what percentage of lands are owned federally across the United States.
Federal areas include federal parks and land reserves, as well as smaller areas like post offices and other federal buildings, as well as the immediate areas around them. They also include properties under federal jurisdiction, which is any agency that crosses state lines as part of its businesses, so airports, train and bus stations are also illegal zones. It also includes any body of water, so lakes and rivers coastlines are also off limits. And many more.
There are numerous areas of federal jurisdiction woven into the geography of every city and state, so even where cannabis is legal, it can still be enforced within the invisible network of prohibition.
Since any agent of the law can enforce federal code, local police who have lost their big money scheme could theoretically set up enforcement rackets in these patches of federal jurisdiction. Doing so would still get them a cut of funds stolen through civil asset forfeiture, so there would be incentive to do so, even if it goes against the will of the citizens in their state.
This is just more evidence that our federal government is not a government of the will of the people, but of itself and the special interests who direct its fangs at the citizens for their own agendas and benefit. And police are the fangs of the vampiric ruling class, who will feed off the victims of the drug war until they are able to institute enough laws to control a profitable monopoly on cannabis themselves.
Legalization is a racket, decriminalize it.