This is a good question. Perhaps it is as simple as this is the leadership culture in China. Their great leaders are firm, are tough, do not tolerate dissent. And maybe people respect them for it.
"I don't know" is the real answer, but here is my guess.
My Chinese friends are incredibly social, incredibly loyal (to each other), trustworthy (to each other) to a fault. They may be ready to submit to an irresistible power, but if they feel they could resist, and somehow benefit their group, they might resist. They love China, they know a strong government is a necessity, they might not particularly care who that government is run by, and might be happy to help replace one dictator with another.
I think the social nature of the culture is the key here. Americans often try to stand out and be independent. Chinese seem to see themselves as part of a group, and they are very good at self-organizing even large groups of people. While the government is in power, that is their government. If it seems like the tide of the opinion of your group is we need a new government, maybe they'll take the streets en masse (like tiananmen square). So maybe the culture means that 99% of the time everyone is peaceful and cooperative, and then that 1% of the time everyone is in the streets burning down the governors house. I don't think anyone would enjoy mob rule, so maybe even the mob would tend to replace a strong ruler with another strong ruler.
These are just my thoughts based on the people I know.
But I think the Chinese government has always lived in fear of the mob. Their biggest threat has never been an outside power, but their own people. There are an incredible number of people living in a small area. This explains the one-child policy in my mind, too many people == not enough food == mobs in the street. So, perhaps as simply self-preservation, the government has 1) limited their population 2) ensured constant economic growth 3) limited the ability for a mob to form at all by controlling communication 4) tried to instill national pride and patriotism whenever possible.