Manchurian Candidate

Sinatra's presence in the army in The Manchurian Candidate is a greater force than in From Here to Eternity or Kings go Forth. In From Here to Eternity Maggio is at the bottom of the army totem pole, receiving scut work and racial slurs from his superiors. In Kings go Forth Sinatra plays a higher ranking officer, but the plot focuses less about the army and more on the relationships between Sinatra, Natalie Wood, and Tony Curtis. In the Manchurian Candidate Sinatra is taken seriously by the army and it plays an enormous part in his life. Once the army determines he isn't having insane dreams he becomes a leader in the investigation of Raymond Shaw. Sinatra provides the key needed to crack the Shaw mystery because he was brainwashed as well, but refuses to accept his thoughts as truth. Without Sinatra Raymond would not have been able to break the mind control.
I have a hard time deciding what direction the politics of this film move towards. On the one hand the evil comes from the outside from the communist Russians and Chinese. In this sense the film defends American patriotism, lauding our country as the righteous and moral center. But the ultimate evil comes from Angela Lansbury's character of the senator's wife who spreads insipid rumors of communism but actually works for the enemy to promote her own selfish interests. This suggests that evil comes from within the American system a more leftist take on politics.
Overall Sinatra's character is far more mature than any of his army characters in his earlier musicals. He isn't awkward or shy around women, he coolly tells Janet Leigh that she's sexy. The romantic relationship really isn't the focal point of the story at all, unlike his musicals. The plot focuses more on solving the mystery than any petty relationship.