Is soy milk in America similar to the type in East Asia?
East Asian soy milk and American soy milk taste very different, and not just because of added ingredients like sugar and emulsifiers. 

Soy beans contain an enzyme called lipoxidase, which breaks down unsaturated fatty acids into shorter chain lipids. For American markets, manufacturers presoak the beans in solvents such as calcium hydroxide in order to destroy this enzyme. After the enzyme is gone, the solvent is deactivated with an acid to form a neutral pH product. In East Asian markets, no one bothers with this added step, and just leave the lipoxidase in there.

Why the difference? Taste, mostly. Remember The shorter chain lipids mentioned before? They taste, well, bean-y. Soy milk manufacturers like Silk found through trial and error that Americans want their soybean milk to taste more like milk, and less like soybean, so this bean taste must be neutralized.

For East Asian people who grew up drinking soybean milk, soybean milk needs to taste like, well, soybean.