The question at the border is "Have you ever visited Iran?", Not "Do you have a stamp for Iran in this passport?".

Since passenger lists on flights around the world are pretty much public information, the US immigration services will know exactly where you have visited in the past, and could totally put you in prison for lying when answering the question.

> The question at the border is "Have you ever visited Iran?"

Is that something only people on ESTA get asked? Never heard of people on visas being asked that.

They ask that questions also during student or work visa issuance - and even during the greencard (adjustment of status) and naturalization processes. They don't ask it every time you enter with these visas or statuses however.

But as a US citizen you will never be asked. And better yet if you are a dual citizen like me. Then you can travel on your other passport to the places the US finds to be undesirable.

I think green card and naturalization ask about travel in the last few years. But they don't ask about travel prior to that, and they don't ask about Iran specifically.

True - I think it was 10 (or was it 7?) year of travel history, but I'm sure Iran would raise some flags.

Still requires you to lie on the ESTA form, which is not necessarily a good idea. (i.e. if you lie and get caught, that's worse than going through the visa process)

Sure, simple answer: don't carry both passports at the same time. Pretty sure Iran (an the other countries on the US blacklist) don't exchange travel information with the US.

and don't appear on any travel manifests other countries share, and don't turn up on any other tracking, and ...

Two different passports, only carry the right one: easy. And unless US border police is checking any, potential, Iranian travel data the NSA collected I don't see the problem. Confidently telling those border police officers you've never been to Iran seems to be the trickiest part. But hell, it works just perfectly fine for everyone travelling to Israel and any Arabian country, so...

No it doesn’t. Israel doesn’t routinely ask you if you’ve been to Iran, if they did, you answer tru fully if you know what’s good for you. Same if you go to Saudi.

The US specifically asks you if you have travelled to those countries. You can either lie, and that’s a serious risk at being jailed, deported, banned from ever going again, and having issues going to other countries, or you can tell the truth.

No photos of yourself there, no references to having travelled there anywhere in the Internet….

The same is in Norway, although one have to justify it. For example one cannot get a visa to China if one has a stamp from Taiwan. So if one needs to travel to both often, then one can apply for the second passport.

I don’t remember China asking if I’ve been to Taiwan. I’d be surprised too - there’s direct flights between the two. That said I normally visit China on a 168 hour transit visa and fly via Hong Kong, Tokyo or Seoul rather than the hassle of applying for a visa.

> For example one cannot get a visa to China if one has a stamp from Taiwan

I am quite sure that this is not true.