Originally Posted by
despegue
Where I have been is non of the US damn business.
2 passports works and is even recommended by my authority.
Just like when visiting Israel, Saudi, Iran for the job, 2 passports to avoid trouble.
Legal.
By the way, Roadster280, how exactly will the US find out that I ever did a layover in Khartoum?!
Quite right, as long as you don't intend to visit the US, then it remains your business. But if you want to visit the US, then you have to follow the rules set by the US.
If you are found to deliberately lie to the US immigration authorities, they will have a sense of humor failure and you will be denied entry, banned from the US for a period, and forfeit the privilege of traveling visa free. That's the least sanction you can hope for.
Whether or how they find out is immaterial, and I have no idea how they do that, but it doesn't seem beyond the wit of man to compare computerized records (like the ESTA itself).
The old green I-94Ws had seemingly silly questions on it like "Have you ever committed an act of terrorism or supported a terrorist organization?". I highly doubt anybody, ever, answered yes to that question. But the point of it was not to have someone answer it honestly. It was a tool to efficiently deport or detain those individuals. The act of lying to the authorities is a serious thing in the US. Never mind the actual immigration issue, you've just committed a federal offense by lying to an immigration officer. Clang, mind your fingers.
I'm not making the case for whether it's right or over the top, I'm just explaining how it is. Having two passports doesn't mean you can lie on one of them.