I do, however, see your dilemma. You don't want your resume getting trashed because they assume you would require huge immigration and international relocation costs. It costs a heck of a lot of money for a company to hire a person who will need immigration support. You want to make sure that they understand that you are a US citizen (or are already legal to work in the US), and, therefore, will not cost them money that they don't have. (Now, it's illegal to discriminate on the basis of national origin, but it's not illegal to discriminate against people who aren't legal to work in the US.)
Now, if and when you are filling out a formal application, they will have a box to check that asks if you are currently authorized to work in the United States. But, many companies don't give you the application until you've passed the resume and phone screens.
So, here are two possible work arounds:
Give your current address as well as a US address. As a student, it's perfectly acceptable to put down your parents' address as a "home address." This will tell the recruiter that you are from the US without broadcasting, "Hey, I'm a US citizen, so hire me!"
Use your cover letter to explain. Cover letters include things that are not on your resume. This could easily include information such as, "After spending 4 years in London, I am looking forward to moving back to the United States." Or, "I am planning a move back to the United States in June, and will not require relocation assistance."
This way, it's clear to recruiters and hiring managers that the United States is your home and it won't cost them a fortune to hire you. Plus, you won't have the need to put your citizenship information on your resume directly.
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