Cruise plays the role of a stereotypical all-American boy, born straight out of an idyllic nuclear suburbia. Nonetheless, he is swept up in the (somewhat justified) anti-Communist sentiment at the time of the Cold War... And voluntarily signs up to be sent to a hostile alien tropical jungle, far from, frankly, where he belongs.
His naivety is quickly shattered upon emergence of war's ugly head, and most of all: the tragic consequences of physical disfigurement. Back at home, he is neglected to a slum for veterans, full of disenfranchised coloured staff who berate him for his alleged white privilege... Meanwhile Cruise's character doesn't even have the privilege of being able to jack-off due to his permanent spinal injury from war. The conditions are abhorrent and are enough to gradually disillusion him about the war and his country.
Later, he joins the anti-war movement against the Vietnam War and is met with scorn and ostracism by the silver-spooned political class. His family tries their best to support him, but nonetheless is helpless to treat his underlying injury. They are not able to reconcile their differences with their son's newfound connection with the anti-government drug-addicted promiscuous hordes of "peace-loving" hippies... The recent past's version of the perpetually offended social justice chip-shouldered hair-dyed bohemians of today. He ends up fleeing to Mexico, where he discovers a wasteland of downcast prostitution and empty debauchery, which leads him back to the United States.
Interestingly, Cruise had also starred in Top Gun a few years prior, which is arguably the total opposite in tone to Born on the Fourth of July. In the end, the movie accomplishes its bleak portrayal of the treatment of disabled veterans by both American society and its government. However, it is an incredibly loud film... Literally and figuratively. It need not be, for the visuals, acting, and background alone is more than sufficient. The deafening tone thus detracts from an otherwise well-performed and directed war film. Cruise is both a wonderful choice for the character (of whom is loosely based off the real world Ron Kovic, with considerable artistic liberties) and executes his role perfectly. Cruise is really what makes this film work, and with the well-selected supporting cast!