Soren Kierkegaard had a theory about the angst-rich idea of identity, the malcontent and drudgery that made T. Yorke want to explode. "Ceasar or nothing!" yells his metaphorical man, a man who so desparately wants to be not-himself that the mere existence he lives as himself screws grief to the seat of his drawers. He longs for this most lofty of titles as his most swayed opposite, the most extreme version of his would-be self (all the better for the histrionics, my dear); his lack breeds a despair that creates a "disrelationship" between the self and the concept of self. In body, he is himself, but in his mind he is the would-be Ceasar self, and appears as yet another self to others; these schisms are a breeding ground for neurosis and Psych undergrad theses.
This in mind, meet Travis Bickle (Robert De Niro). The man has drank and seen the spider, alright. He spends an inordinant amount of time shuffling the grime of New York around in the back of a taxi, kvetching in voiceovers about their lack for scruples while off-clocking the same sins himself. It is not so important that Travis is a war vet--it is mentioned he was a Marine, and he dons his battle jacket--but more that he is a man who has fought and not won, taken causes and lost. He's a ship of dynamite with an anchor that barely drags the bottom of a bathtub (he never mails those letters, you know); he is ready to pop off, son. Pop off! His directionless agitation is shawled around his shoulders. This is why an earlier shot of Alka-Seltzer fizzing violently in a glass of water is so apt.
His Kierkegaardian trip is a woman, Betsy (Cybill Shepherd); he wants to be her savior from a perceived senatorial captor (Palantine) and her life of prudish blonde snobbery. Failing to do this, he grabs his angst by the wrists and drags it around; he stomps reason out through the soles of his shoes. Palantine now becomes his Ceasar or nothing, but for Travis that disconnect bloodies itself, trades dirty cash money for guns, puts in one socket an evil eye and gets to work. The suit up plays out over the increasingly anxious and frenetic score of Bernard Herrmann, relating the appropriate atmosphere as Travis primes his weaponry for the task at hand with an almost nightmarish calm; the erratic harps and strings give way to the sultry saxaphone earlier assigned to Betsy as he scrawls a boyishly scripted letter to Iris (Jodie Foster), a heavyhanded bit of oratory foreshadowing.
The suit up scene leads to Travis standing at the Campaign meeting, very obviously juxtaposed with two signs warning against trespassing--yet there he stands, very much the pedestrian squirreling in, clapping over-enthusiastically for a man he intends to brain with the business end of a bullet: the viewer is so very much aware of his isolation now, and has no choice but to side along with him. If New York is the City of Dis, Travis is Virgil, and the viewer a cringing Dante. Shit goes awry with Palantine and Travis, still completely engulfed in his desire and need to be more than himself, tramps his perverted mohawk to the pimp district and will accept no bitchassness.
The result is several shades of saturated bloodshed and an ending that questions more than it soothes--in its most readily readable way, Travis has seemingly become the would-be Ceasar of himself; the Ceasar here being the media hero, the darling of thanks, having saved a young runaway from herself and a pimp (Harvey Keitel) sporting some seriously questionable hair. His angst is seemingly sedate enough for him to be back in his cab, picking up fares in an area teeming with clean clothes and proper boundaries, and he totally blows off the broad who held his length in a homicide-inspiring lovegrip. But listen: when the worm has eaten the apple, the apple is in the worm. That flat affect and tilt of the rearview mirror signal the creaking door of a horror story; he is still himself--nothing.