The US House of Representatives’ bipartisan amendment to prevent the Department of Justice (DOJ) from interfering with any state implementing medical marijuana legislation may not be such a big step toward ending prohibition.

The single sentence amendment, that won in the House on May 28 by a slim 219-189 margin — it needed 218 votes to pass — said that the DOJ can’t use any of its $27.8 billion funding for 2015 to mess with the medical marijuana programs in 33 states named in the text.

The amendment to the 2015 Commerce, Justice, Science and Related Agencies Appropriations Bill (CJS) was heralded by members of Congress and the media as a historic occasion. And why shouldn’t it be? After all it was the first time the House successfully rolled a significant change in the country’s broken marijuana enforcement policy.

But, needless to say, such a blunt instrument is far from being a reality.

The Senate is the first hurdle, and the odds are already not looking good. On Tuesday, the Appropriations Subcommittee approved a version of the House bill the medical marijuana amendment was attached to — without any mention of defunding DOJ enforcement.

That’s not much of a surprise, considering committee’s vice chairman, Senator Richard Shelby (R-Ala.), has said in the past that he would oppose taking money from the DOJ’s enforcement of medical marijuana.

And several sources in the capital familiar with the House marijuana amendment told VICE News that it was unlikely other state senators would attempt to defund the DOJ’s marijuana enforcement — possibly because no US Senator has supported ending marijuana prohibition, and there are numerous Republicans who can’t let go of the so-called “War on Drugs.”

Without support in the Senate, the fate of the amendment lies with what’s called a conference committee made up of Senators and Members of the House who will hash out the differences in the larger CJS bill, including the marijuana component.

Yet the Senate is unpredictable.

If the marijuana amendment makes it through the conference — which is an enormous if, because partisan bickering and conference committee personalities (which have not yet been selected) play a significant role in its decisions — it would still need to be signed by President Obama.

Once on the president’s desk, it’s hard to say whether or not he’d veto a bill that included a clear expression of what the majority of Americans now want.

On the one hand, the president has said that he regards marijuana consumption as a "vice." "As has been well documented,” he told the New Yorker earlier this year, “I smoked pot as a kid, and I view it as a bad habit and a vice, not very different from the cigarettes that I smoked as a young person up through a big chunk of my adult life.”

But, on the other hand, President Obama has a lucid understanding of the destruction and societal corrosion that’s brought about when a public health concern is handled by the justice system.

“Middle-class kids don’t get locked up for smoking pot, and poor kids do,” he said. “And African-American kids and Latino kids are more likely to be poor and less likely to have the resources and the support to avoid unduly harsh penalties.”

In that sense, the president dead on. Even with the attorney general’s recent guidance on marijuana enforcement — widely misunderstood as suggesting the feds weren’t going to go after businesses following state law, when in fact marijuana is now simply much a lower enforcement priority, but still enforced — the government’s historical approach has caused immense damage even to communities that have ended the prohibition on medical marijuana.

The most recently available data indicates that about 750,000 people were arrested on suspicion of marijuana related crimes in 2012, and of that 652,500 were nabbed for possession — the vast majority of whom are young people in their teens and 20s.

Of those arrested for possession, African Americans are 3.7 times more likely to be arrested for marijuana possession than white people, according to the ACLU. And in terms of Latino arrest numbers, we just don’t know. That’s because the FBI’s Uniform Crime Reports system doesn’t track whether an arrest is Latino or not.

Then, of course, there are the thousands Americans whose lives have been irrevocably altered by government captivity — lost jobs and income, and the dehumanizing effects of incarceration to name a couple of consequences for a crime that is increasingly regarded as entirely avoidable collateral damage of a drug war that the US lost years ago.

Lastly, it’s questionable whether or not the new piece of legislation will have the teeth its supporters are claiming. A close reading of the bill suggests that in fact, the amendment would prevent the DOJ or Drug Enforcement Administration only from using the new cash to sue states such as California over the medical marijuana laws, in an attempt to repeal them. (Something the DOJ has agreed to do already.)

It may not actually prevent the DOJ from hunting down and locking up those who participate in the ever-growing marijuana business. But at this point, the DOJ is staying silent, and didn’t return a number of phone calls I made and emails I sent over the last week.

So, cannabis advocates undoubtedly won a victory in the House last week, but ending prohibition is still likely a long way off.

Follow Max Cherney on Twitter: @chernandburn