Can I leave the airport and explorer while I'm waiting for the next flight?

I'm a U.S. citizen and I'm flying from Newark, NJ to Seoul, Korea, but there's 1 stop in Tokyo, JP before I arrive to Seoul. The time in-between my connecting flight from Tokyo to Seoul is from 3:25PM to 10:55AM the next morning. With so much time, I would like to explore Tokyo! Do you think they would allow it?