You are making this much more complicated than it needs to be without any practical relation to what actually happens when you travel. Handing two passports to every official you see in the airport is only going to confuse people who aren't familiar with dual citizenship and waste much time.
Originally Posted by
alanR
US rules require US citizens to enter & leave the US on their US passports . . .
Wrong. You don't need to present anything to
leave the USA-- even if you aren't a US citizen.
Originally Posted by
alanR
. . . if you hand over any other passport you probably will have to explain why you have no sign of lawful entry into the US.
Hand over to whom? The immigration police that they have stationed at the jetways of all flights out of the USA?-- oh wait, there's no such thing. The airline isn't going to care how someone "got in" to the US.
Originally Posted by
alanR
So you'd have to show both passports but the Israeli one will get you onto the plane.
Actually, only the Israeli passport would need to be shown. The airline only cares that you will be accepted where they are flying you-- not how you got into the country of the origin of the flight.
Originally Posted by
alanR
On the return you'd need proof that you'd be allowed into the US, so you'll have to show your US passport, but then you'd be asked "where's your visa", so you'd have to show your Israeli passport.
Again, there is check-in and immigration. It is ever so simple. At check-in for your flight back to the USA, you present your USA passport to prove that you will be admitted into the USA. The airline isn't going to page through your passport to see how you got into Russia-- nor would they care.
At immigration on the way to the gate, you give them your Israeli Passport so they stamp you out of the country. You don't need to give them your US passport because they don't care if you will be admitted where you are flying to. These are two different processes with two different purposes and the two need not be confused.
Originally Posted by
alanR
So the simple answer is that you'll have to travel with both passports and hope the Russians don't decide to be stroppy
Well, if you only show the Russians your Israeli Passport on the way out, that wouldn't really be a problem now, would it?