The legislation has one major hurdle to over come, Posse Commitatus. SCOTUS would never overturn Posse Comitatus because it very strong standings in the Constitution. These are Article III Section 3 treason laws. Congress could repeal Posse Commitatus. But that would essentially legalize treason. Congress won't legalize something a harmless as marijuana. I don't think they would be able to get away with legalizing something as harmful as treason. But these days you never know.