It's interesting...we spent a good part of this summer in Europe. Several cities and countries, including both traditional tourist cities (Paris, Venice) and less traditional spots, visiting friends in rural France, Slovenia, and Italy. Whenever I travel, I always tend to observe the behavior of other tourists and locals alike...in part because I attempt to behave well and in part because it's fun.
One thing that I found interesting, and I've noticed on several of my more recent trips abroad: the Americans have generally been reasonably well-dressed, very polite, quiet, and generally in control of their liquor when they drank. I saw a lot of "bro tanks" and quite a few drunken guys at cafes/pubs, but they were generally tourists from the European region, not Americans. Where we met Canadians, Americans, or even the occasional Australian, they tended to be families or maybe an older couple traveling without the kids. Pretty tame.
So I think the Chinese are beginning to go through what we did in the 1970's and 1980's. Millions of Americans suddenly had access to affordable jet travel, so a bunch of us went to Europe and were Grade-A a**holes when we got there. Now we've had a full generation to think about what makes an "ugly American", so we are (for the most part) a little more self-conscious when we travel.
Now the Chinese have a similar effect: a rising middle class, tens of millions of people suddenly with access to affordable international travel. It might take 'em a generation to get it sorted out, which would make them no different from us.
One thing is for certain: it's a huge market, and I hope we can attract a lot of those tourists to the U.S. I hope we - and this includes our airports, airlines, border security, etc. - aren't such a**holes to them that they decide to go elsewhere.