If you’d hoped that the Trump administration would respect states recreational marijuana laws, then I have some bad news. Disappointingly, the White House recently promised “greater enforcement” of federal marijuana laws.
As you probably already know, marijuana is still illegal at the federal level in the U.S.
White House spokesman Sean Spicer told reporters on 23 February 2017 that the administration would crack down on recreational weed in states where it has been legalized. 
The Obama administration took a very hands-off approach to marijuana, declining to enforce federal laws so long as states regulated the marketplace. Toward the end of his presidency, Barack Obama expressed support for legalization. 
However, marijuana advocates expressed deep concern for the future of legalization when President Trump announced Jeff Sessions as his pick for attorney general back in November. Sessions has been very vocal about his disapproval of marijuana and was even quoted as saying that “Good people do not smoke marijuana.”
President Trump himself expressed support for state marijuana laws while on the campaign trail. While campaigning in Nevada in 2015, Trump said:
“In terms of marijuana and legalization, I think that should be a state issue, state-by-state.” 
But in his remarks to reporters, Spicer called marijuana a scourge and repeatedly linked marijuana use to the nation’s opioid epidemic, suggesting that marijuana is a gateway drug to harder substances.
“When you see something like the opioid addiction crisis blossoming around so many states … the last thing we should be doing is encouraging people. There is still a federal law we need to abide by in terms of when it comes to recreational marijuana and other drugs of that nature.”
“I do believe that you’ll see greater enforcement.”
Marijuana is a Schedule I substance, so “other drugs of that nature” likely refers to other substances on that list, including heroin. Spicer is literally comparing a plant to man-made, deadly heroin. Marijuana has yet to kill a single human being. Heroin, on the other hand, is lethal. In fact, CDC data shows that heroin-related overdose deaths have more than quadrupled since 2010. In 2015 alone, heroin overdoses claimed the lives of 13,000 people in the United States.
Ironically, Spicer’s views on cannabis stand in stark contrast to those of the federal government’s. Earlier this month, the Drug Enforcement Administration (DEA) removed several marijuana myths from its website, including the myth that marijuana serves as a gateway drug. The agency also removed references to cannabis causing psychosis, cancer, and decreased cognitive function.
The DEA hasn’t busted pot businesses operating legally under state laws in years. The Obama administration issued an administrative policy ending such federal raids, and in 2014 Congress banned the agency from using federal funds to go after medical marijuana operations operating legally under state laws. 
The “best-case” scenario, short of respecting states’ rights, would be for the administration to crack down on the illegal transportation of cannabis between states or raiding a few dispensaries. The nightmare scenario would involve filing injunctions seeking to nullify state legalization laws, Los Angeles Times reports. 
Incidentally, a new Quinnipiac poll also came out on February 23, showing that 71% of Americans surveyed are opposed to the kind of enforcement action Spicer hinted at. Additionally, the poll found that 59% of Americans are on-board with full marijuana legalization.