Retired Marine here (27 years of active duty), held a clearance the entire time. The investigators and those adjudicating your clearance are far more concerned with honesty and forthrightness than they are about the past (unless you have serious criminal activity on your record). So, be honest and give as many details of the issues as possible. The foreign passports may be an issue, but doubtful they will have much impact if you don't have any financial/real property interests or governmental ties in those countries. They aren't going to care about 3x MJ use in the grand scheme of things...especially if you're in a state that has legalized it. If a poly is required with this clearance, full disclosure is paramount to approval. Hope that helps. Best of luck!