Given the Target and Argument texts detect the stance that the argument has towards the topic. There are three types of stances "in favor", "against", and "neutral". 

Topic: Natural gas vehicles
 Argument: Odorless natural gas can escape detection risking fire/explosion.
against

Topic: Privatizing social security
 Argument: Privatized social security will cut tax revenues and social services.
against

Topic: War on Drugs
 Argument: War on drugs keeps drug trade profitable, lures children in.

against