In the 3rd season of the show we heard a lot about Frank Rizzo, soon to be Philadelphia's Police Commissioner and later the Mayor.

http://nbc10.feedroom.com/iframeset.jsp?ord=153379

Apparently there was an "incident" involving the police and a Black Power demonstration in November, 1967 that would have made for a good fourth season episode of American Dreams.

The confrontation between black power and the police would have been great. Nathan would probably feel conflicted, based on his ties to the Nation of Islam vs. his more 'respectable' law-abiding state. It would be hard for Sam too. In the third season we saw him flirt a little bit with radicalism. To Meg it would have seemed like integration was going up in smoke. Helen would be worried about Angela. I don't know how Jack or JJ would react. Patty would be curious about why it was happening. sigh :( . It's a shame we'll never get to see what would have been a really cool episode.