I'd seen bits and pieces of this over the years, but never the whole thing straight through. Bronson is Paul Kersey, a successful New York architect in a happy marriage, with a son and daughter-in-law. Right away the film telegraphs its POV about violence, when one of Kersey's coworkers calls him a knee-jerk liberal and, knowing it's a Bronson film, we can see that an awakening is about to happen.
For those who don't know the story, I'll make it brief. Kersey's wife and daughter-in-law are viciously attacked by a trio of hoodlums (including a young Jeff Goldblum) in Kersey's apartment; his wife dies and the daughter-in-law is left so emotionally scarred that she never recovers and ends up in a sanitarium. In the early scenes, before and after the attack, we see a crime-infested New York where violence is casual, everyday, all over - and a police force that is powerless. Bronson undergoes a slow metamorphosis - to the credit of the film, he clearly has doubts about what he's doing - as he decides to take the law into his own hands upon finding that the cops can't do anything. Interestingly, he never really speaks out against the police though his son more than once says "nobody can do anything." At first he just puts some rolled-up quarters in a sock and carries it with him as insurance, at one point fighting off an attempted mugging - but after a lengthy trip to Tucson where he makes friends with a client who turns out to be a gun collector, he decides to arm himself seriously, and a one man (and five movie) war on crime begins...
This got lambasted by liberal film critics when it came out, of course, just as Dirty Harry had three years previously, but what's interesting about it today is how low-key the attacks on liberal values are, and in fact the film really doesn't go after anything except on-the-street violence. Of course it completely ignores class and race issues, except for one brief comment where somebody at a party mentions that there are more black criminals than white - it basically just treats all "criminals" as scum who enjoy preying on their victims. It does get a bit more disturbing as it goes along, and we see Kersey acting first, deliberately getting himself into situations where he might be in danger, and then blowing people away before they even have a chance to go at him. No question that the morality here is decided skewed to the right, but as I say, not so much as you might expect given its reputation. Probably the most extreme part is at the very end, when the rather sympathetic police detective (Vincent Gardenia) who's been in charge of hunting down "the vigilante" lets Kersey go - but given the vision of the city this film gives us, this isn't really unexpected.
The film-making though is quite solid; one thing Winner can do is propel a story forward, with very little in the way of needless exposition or explanation. The New York locations are well used, and Bronson is...Bronson. Great music by Herbie Hancock.