Role-wise, actor
J.T. Walsh was pretty much a professional scumbag, except for his uncredited cameo in "Misery", just about every character he played ranged from criminal to despicable to out-and-out evil.
Dickerson fills the latter bill, as his act of sending an unarmed Adrian and Garlick straight into VC-occupied territory is basically an act of attempted murder or treason, if not both, and in real life he would most likely be court-martialed. Then again, in the film's end, that might have been why the General was sending him to Guam!
Other lowlifes played by Walsh include the D.A. who wanted to put Kris Kringle away in 1994's "Miracle On 34th Street" remake, a corrupt Internal Affairs cop in "The Negotiator", and Kathleen Quinlan's kidnapper in "Breakdown". His last role before his death was 1998's "Pleasantville", where he played the tyrannical mayor.