Oddly enough some of America's best written shows originated in England. That said I can think of some great American shows. MASH, All in the family, Mary Tyler Moore (one of my favorites), Seinfeld to name a few. Today I think Law and Order SVU continues to bring to light some good issues, if not a bit disturbing. Personally though I watch a great deal of British shows and now they even have a Law and Order UK. Granted you could make the argument that American TV is brainless drivel but every now and then something really good manages to creep through.

Two roads diverged in a wood, and I�
I took the one less traveled by,
And that has made all the difference.