Yep- We Yanks do play "proper" Rugby Union. It's still a bit of a "fringe" sport, but getting more & more popular. In fact, the US of A is the last winner of the Olympic Gold Medal in Rugby. 1926 I think.
If the US ever gets serious about rugby the way we are "serious" (read: throw money at) other sports, look out World Cup. I of course will be a crippled old relic grousing on the sidelines & reminiscing about the "good old days" when we had to change into our kit in our cars, how our co-workers scorned us on Monday mornings when we limped/lurched/staggered into work with mashed-in faces, and how nobody understood our foulmouthed singing in bars while covered in mud, blood & other substances. It will all be on MTV & be very stylish and they will ruin everything and I will hate them for it.