On the other hand, I'm not sure if people in general are that quick to help out in emergencies, especially if they can tell themselves that somebody else will handle it.
In 1993, I was driving down Lawrence Blvd. in Chicago, and was stopped at a red light at Western Blvd., third in line. Out of the corner of my eye, I saw somebody sprint across Western trying to make the bus at the corner. Bam! She got hit by a car, rolled up on the hood, fell off the right side of the hood, and landed on her head in the lane of traffic.
"Wow," I said to myself. "If there weren't so many pedestrians, bus passengers, and other drivers closer to her than me, I really ought to get out and drag her out of the street before somebody else runs her over and finishes her off." I waited maybe two seconds, but nobody else moved toward her. So, I grabbed my keys and sprinted about 100 feet to her, waving my arms to alert drivers not to hit us. The young woman had a golf-ball size lump on her skull, but was moving enough, trying to get to her knees to crawl, to show that her neck and back weren't broken. I hauled her to the sidewalk.
In May 1999, I was walking south along the west bank of the Chicago River toward, as I recall, the Madison St. bridge at 6 pm, in a huge crowd during rush hour. I saw something plummet off the bridge, which is about 50 feet high, heard a splash, and saw arms waving frantically in the cold river. Probably about thousand bystanders gawked at the woman in the water.
I ran a half block down to the bridge, yelling for somebody to call 911 (I didn't have a cell phone), then sprinted across the river, passing hundreds of people, to the lifesaver ring attached to a rope in a glass case at the bridgetender's tower near the corner of Madison and South Wacker. That's probably a few hundred yards, and I'm slow, so that must have taken at least 90 seconds, but when I got to the life preserver, nobody else was there. (I am an old Boy Scout type, so I had noticed the life ring years before; I imagine most pedestrians never paid any attention to it.)
I whacked ineffectually on the glass with my casual leather shoe a few times, but then a well-dressed passer-by gave me his umbrella and I smashed the glass, wrecking his umbrella. (He didn't mind.) I then ran back to the middle of the river, tied the rope to the railing, yelled down to the woman, and dropped the buoy (managing to not clonk her on the head with the lifesaver, which would have been ironic but unfortunate). She grabbed it and hung on, and about 5 minutes later a fire department boat arrived and hauled her in.
This was an upscale crowd, too, mostly Loop office workers on their way to the Northwestern train station to ride home to the nice suburbs. But the guy who volunteered his umbrella for me to use in smashing the glass was the first other person I noticed taking any self-initiated action in the first 100 or so seconds.
So, while I imagine the Chinese do need to get better, it's not like Americans are all that forthcoming, especially when there is a huge crowd of others who might get involved first.