Obviously, not everyone thinks tall men are attractive, but there's a general cultural understanding that height is a preferred feature.
I'm wondering because as China becomes richer and more prestigious in the global consciousness, being shorter -- Chinese people are, on average, shorter than Europeans -- could become a more attractive quality.
Of course, some of the relative shortness of Chinese people is due to nutritional differences, but a substantial portion is genetic.
Just to add on to what has already been said, the attraction of height can be attributed to our instincts. The height of a nation's population can be connected to the health and power of said nation. In fact, the richest countries are also the tallest. This can be related to certain peoples in history and why taller is considered more attractive in terms of health.
Just some background, some diseases of the past (and present) were known to stunt growth, therefore many people of the past were quite short, especially our earlier ancestors who migrated frequently and dealt with extremes in weather. When people began to live stationary lives and a warm spell in Europe extended the growing period for food in the Middle Ages, people became taller. However, height dropped towards the 18th and 19th centuries when people began to migrate once again, which only aided in spreading diseases. In the early 1800s, the Cheyenne people of North America were considered the tallest, with an average man reaching about 5 feet 10 inches. They were taller than the Assiniboine people to the north in Canada because the Cheyenne had milder climates which allowed them to hunt for longer periods, therefore their health was considered better.
Now, about the attraction of height in terms of health, women are instinctually looking at men as prospective mates as much as men are looking at women. It's something thats just in our DNA. Height in men equals better health as much as larger hips on women do. If a woman has larger hips, it is believed that she'll be able to carry more healthy children (or at least it was in the past).
Height can also be attributed to wealth. Taller has always been considered better. Every city wants the tallest tower. Every king wanted the biggest castle. Height equals power and wealth because it is believed that taller people can afford better food and therefore be healthier. In fact, up to one third of Fortune 500 CEOs are taller than 6 feet 3 inches. Women instinctually look at taller men as being more powerful and wealthier. Therefore, the taller man would make a better mate as they believe he would be able to take care of his family. Of course this outlook is changing as more women become independent, but that instinct is still there!
In the future, the Chinese may begin to grow as their wealth extends, although as you said, their nutritional differences could keep them at their current height. But you have to think of the Chinese women who are still shorter than the men, so height still comes into play when looking for a partner.
What is all really boils down to is survival and the ability to pass on our genes to healthy children. Height equals health and power which then makes taller men more attractive.
I hope this helps!