I hope none will take this as racist but there may be very good reasons why young black males might not be attracted to a branch of the service that is likely to involve a lot of time not just on the ocean but in it as well.
Since blacks are attracted to the military it sure can not be that they don’t want to serve. It could be they just don’t want to serve in the Coast Guard. And all the incentives and demands in the world will not change that.