Singer Joe Strummer noted in a 2002 interview with Uncut magazine that the title "Hate and War" was a direct reversal of the hippy phrase "Love and Peace," done to illustrate the contrast between the optimism and hope of the late 1960s and the grim reality of Britain in the '70s. "It was a good punk rock blast to have a song called that" he said.
In a 1991 interview, Strummer remembered that he "wrote the lyrics in a disused ice cream factory I'd broken into. It was just behind the Harrow Road in Foscote Mews. I wrote it in the dark by candlelight and the next day took it to Rehearsals and Mick put a tune to it."
The lyrics in question are an angry indictment of everyday working class life in London, and a rallying call to toughen up if you want to survive in the mean streets ("I have the will to survive, I cheat if I can't win. If someone locks me out, I kick my back in, an' if I get aggression, I give it to them two time back").
It also controversially uses racist terms such as "wops" and "Kebab Greeks." The lyrics are ambiguous as to their usage, although it would appear the song uses these terms to add to the gritty realistic feel of urban London at the time where such language may well have unfortunately been commonplace.
"Hate and War" was first introduced into The Clash's live set on the Anarchy tour of 1977, and was dropped by 1978, but after that would reappear every so often on tours - the Pearl Harbour tour in 1979 (and on their appearance on the Alright Now TV show), occasionally in Europe in 1980, once in Newcastle in 1982, all of their 1983 US Festival warm-up shows (and the festival itself), and their last festival shows in the summer of 1985 with Strummer handling all lead vocals after original singer on the song Mick Jones had been fired.