The Communist are looking for revolution here in the USA. This topic could go several directions but my first thoughts were that anyone seeking to start a movement or revolution usually targets the young idealistic of a society but Communist have been around for a long time now.
My other thought was if these people truly believe communism is such a better system then why fight a huge battle and fight in an attempt to overthrow your government when there are already several communistic countries out there. These folks could easily go to Cuba, China, or even North Korea but it's very doubtful that any of these nations would have them or leave them alive for more than a few months.
No other government or system of government has ever been more beneficial to the majority of its citizens as has that of the United States. Communism only is realistic as an ideology and always fails when implemented regardless of where it's done.