It doesn't matter if you declare it. Apparantly somebody paid off a congressman to step up looking for fake goods. No checking for nukes coming in through the ports, but very important to US security that anybody with a fake gucci bag be stopped.
Actually they will let you bring one of anything in. At least that was the speech last time. 1 jacket, 1 watch etc. I guess if you have two it means you are selling them on ebay. Also some brands must have paid more and the enforcement is tighter. (Northface)
Maybe after the elections things will calm down.