1. Marijuana Enforcement Is Costly
From law enforcement, to incarceration and prosecution, the bill continues to add up. According to a study conducted by the Cato Institute in 2010, enforcing marijuana laws cost U.S. taxpayers $8.7 billion dollars!  According to Jeffrey Miron (a Senior Lecturer at Harvard) that total (adujusted for inflation) would amount to nearly $20 Billion dollars in 2017. Will the federal government continue to hemorrhage precious taxes dollars on useless marijuana laws and enforcement when people will continue to smoke either way?
2. The Potential Tax Revenue Is Massive
Say we just legalized marijuana and taxed the industry accordingly. We would generate some serious revenue! In fact, according to a study conducted by the Tax Foundation in 2016, the marijuana industry could generate up to $28 BILLION in tax revenues for federal, state, and local governments!  This money could go towards roads, schools, parks, and other public goods. Obviously the government has had no problem collecting tens of millions of dollars in tax revenue from states that have already legalized marijuana, like Colorado, Washington, and Oregon. Why not collect from all 50 states?
3. Jobs, Jobs, Jobs!
In addition to bringing in large amounts of tax revenue, the marijuana industry will create more jobs than the manufacturing industry by 2020; more than 250,000 jobs according to Forbes.  These are legit jobs that pay well! That is amazing!
4. Marijuana Has Incredible Health Benefits
From treating Glaucoma, to controlling epileptic seizures, to potentially slowing the progression of cancer cells and Alzheimer’s Disease, to pain relief, marijuana seems like a medical miracle. Scientists continue to discover new health perks derived from marijuana, and it is being accepted around the nation and even around the world in numerous medical communities.
(However, there has also been negative effects studied from the ABUSE of marijuana, like memory and emotional changes, and dependency problems. So, if it is used wisely, it is highly beneficial.) 
5. Public Opinion Has Changed
It’s time to accept the changing view on marijuana and legalize it! As of 2016, 60% of American’s support marijuana legalization. With more and more studies being conducted and reported, the civilian population has truly been enlightened, and realizes that marijuana isn’t all that bad. In fact, it is much more beneficial than not. Combined with the other reasons in this article, legalizing marijuana makes a convincing argument. 
3. 250k Jobs