Broderick Crawford's portrayal of Captain Grimes very realistic

My favorite character depiction in this movie was that of Crawford's playing Captain Grimes. If you have any knowledge of the background to that story and in particular, Captain Grimes' history and predicament, you can truly appreciate Crawford's portrayal. Very realistic. When WW2 began, the US Army was quickly expanded and there was a shortage of qualified officers. To partially solve this problem, the army reached down into the senior NCO ranks and gave some of these long-time professional soldiers emergency commissions. Some had limited capabilities as officers. This is more fully developed in Norman Mailer's "The Naked and the Dead" novel (but not the movie based on it).