What is the proposal? I assume your assignment has given you a scenario of some sort and you are to evaluate its practical effect on the current way in which private contractors are used.
In order to do such an analysis, you would need to examine the results of the proposed program and determine how those results would impact the private contractors, the market for the products or services being provided by the contractors, and the comparative costs of the expanded program versus the current system. You might also need to examine practical issues that would impact the expansion - would it be feasible, beneficial, worth the revising of practices and policies that would be required?
Look at your assignment with these considerations in mind. Writing 50 words in response shouldn't be too difficult.