There are two ways the forces could function as a military deterrent: either (1) the U.S. deployment would be large enough to serve as an effective military barrier to a future Syrian military offensive or (2) the U.S. deployment would serve as a "tripwire" to ensure that such a Syrian offensive would trigger a large American military intervention to oppose it.
If the likelihood of getting caught is the greatest deterrent to white collar crime, then Congress should increase the budgets of those agencies whose function is to catch white collar criminals.