How does Aquarius learn to deal with "community" when they have so little empathy?

It is not because Aquarians have no empathy. Aquarius rules the 11th house of friends, groups, ociations, and goals. The 11th house is considered to be what one "wishes for" in life. Aquarius wants all humans of this planet to get along with each other. That is the goal. That is why they are often involved with groups that want to improve our planet. Although Aquarians may seem detached and emotionally distant, they are actually always thinking and others might feel them to be 'detached" when actually all that is going on in their head is another way of doing something. They are future-oriented and their minds are usually going a million miles a second (they are in their own little world) and this may make them appear to be "detached" but the actuality of it is that they are constantly thinking of new ways to solve problems of all kinds. So, yes, you are right on target with your comment that Aquarians detachment is useful in that it allows them to realistically work on the troubles of the world without breaking down with every thought of a neglected and hungry child, the plight of the homeless, or the abuse of the elderly. This big issues are over-riding the sympathetic nature of let's say, Pisces. Many professions at one time or another (esp in medicine, doctors and nurses) have to put their emotions aside in order to do their job. Firefighters, policemen, social workers, forensic investigators, medical examiners, etc do this every day. If they didn't, they would be headed for their local mental health facility and step on it. Good question. Made me think which is great. Good luck and Bless you.