Is Russia dangerous for tourists?

I'm a 6" 1' white male American. I want to go to Russia (more specifically, Moscow, Saint Petersburg, etc.) What you could call cultural tourism. Will I be in any great danger? I heard that Russia is not the safest place for an american. Oh, also, I will be nineteen-twenty one or so when I go, but I like to plan FAR in advance. Thank you for your answers!