OK, thanks for the advice. O/T but where in Syria did you travel to? Just curious! I was in Damascus about 6 weeks ago, I loved it, would definitely go back!(Original post by JCM89)
If you have a passport without a Syrian stamp then definitely use that one. I was subjected to 'additional security' before checking in - a lot of questions about why I'd travelled to Syria (they didn't seem interested in the Jordanian or Egyptian visa stamps) and was I aware that the country was hostile to America and all that. Only held me back about 15 mins but I was stressed as I hadn't expected the additional scrutiny and I was worried they wouldn't let me check in for the flight. I then had the same thing at US immigration. I've travelled to the US several times since - on a new passport - and zipped through with no problems so definitely use the other passport!