When I turned up in LA they were suspicious about why I had loads of stamps for going in and out of thailand from laos, along with stamps for fiji, newzealand and australia. They looked at my bag and said in his strong american accent "is that all you got"
Are they really that bothered about stamps? I'm off to LA in September and my girlfriend has an Iranian and Pakistani stamp in her Passport from last year. Is this going to be an issue?