Yes. If you purchase a phone sim card you get a local USA mobile number (e.g. 202-123-4567). This means that people in the USA (airlines, tour operators, hotels etc) call you on a local USA number, just like you were an American! People back home call and SMS you on your USA number (they'll of course pay the cost of an international call/SMS to your USA number).
Many people ask us what they should do with their Australian mobile phone - click here to read more information.
If you'd like to know how people back home can call and SMS you just click here to read more information.