"The Man of Steel" is Cast, and he's a Brit?

I love Superman, he's in a three-way tie with Batman and Spider-man for my favorite comic book hero of all-time, so I wanna see any new Superman movie being made, and Zack Snyder's movie The Man of Steel has some fantastic potential, being written by David Goyer and produced by Chris Nolan, but I am a little skeptical over the casting of British actor Henry Cavill as Superman himself.

It's not that I don't think Cavill can act, cause I've only ever heard rave reviews about his star portrayal in The Tudors, but am I the only one that thinks it is weird to cast a British person as one of the most essential American icons? Sure, Cavill will probably do great in the role, I mean, he'll do a fantastic American accent and will probably knock it out of the park, but if the producers of Harry Potter can be exclusive about only casting British actors as British characters, then why not cast only American actors as American characters? I don't hate Britain or British actors, I just wonder why so many movies nowadays opt out of casting American actors?

It's a startling trend, I mean Nolan's own The Dark Knight was filled with actors playing Americans who are not American born but hailed from Britain and Australia; as a matter of fact, Aaron Eckhart, Maggie Gylenhaal, and Morgan Freeman, are the only leads from that movie that were born and raised in the US of A. Once again, as long as they do fine in the roles of Americans, I shouldn't care, but what does this mean for the future of American movies themselves when we're having to draw in talent from other countries to make our movies? We'll find out when The Man of Steel hits theaters Holiday season of 2012!