Answer: Yes, of course you can. As long as you have a green card, you can travel anywhere and still be able to come back to the US, but there are paperworks that needs to be filed with Immigration though. But just traveling in the US, yes you can go anywhere in the US, you dont need a passport.
I live in the USA with a Green Card but am a citizen of the UK and a UK Passport holder. I am thus to the USA/US Immigration a foreign passport holder.
Does a Bangladesh Passport holder having USA Green Card need tourist visa for Cambodia
A US passport can be applied for and got only by a US citizen. Green card holder should apply for US citizenship first and then apply for US passport.As a visa or green card holder in US should have their home country passport. A green card holder can fly with green card itself provided abroad visit is for less than 180 days each trip. For more days they would require a reentry permit which they should apply for and get it approved before leaving US.Within US they can use green card or visa document itself.
you will need a passport
Yes, you can. You just have to take your green card along with your Iranian passport.
In the US it is not required for a green card holder to possess their passport, but they MUST possess their green card AND valid identification at all times. Frankly, since they are citizens of a foreign nation it would probably be advisable for them to carry it though.
I live in the USA with a Green Card but am a citizen of the UK and a UK Passport holder. I am thus to the USA/US Immigration a foreign passport holder.
only US citizens can hold a US passport. the resident alien must first apply and complete the citizenship process
Yes, you always need a passport when you travel outside your country of origin.
No, you must consult immagration who will sort you out
Yes, you still need a visa. But it's better if you apply from the US not Iran. If you are an Iranian green card holder, you can visit Canada without visa though. Same with Bahamas, Costa Rica, Bermuda and Jamaica.* Remember to always have your passport with you when visiting these countries otherwise the US won't allow you to comeback with just the green card.
Going to Seattle from inside the US - no. Going to Seattle from outside the US (even Vancouver) - yes.