Really? You don't understand how having a package of drugs intercepted to an address is enough to get a warrant for that address? Any country in the world that would be enough for a warrant to raid. Don't count on getting a love letter for anything more than personal use amounts of schedule III or V pharmaceuticals, marijuana seeds or grey area research chemicals. If customs stops your two grams of MDMA you are probably going to get a visit by LE, knock and talk at the very least but raid isn't out of the question. Customs in USA is part of the department of homeland security and they do counter drug smuggling, counter intelligence and counter terrorism. They can also open any package with out a warrant or order. lol you never heard of customs doing a bust? guess you have not looked very hard.....customs does the vast majority of illegal importation busts. I know of a case where interception led to raid (was a few hundred sheets of LSD) and they arrested every single person at the house (although only ended up charging one I think).