nobody is excusing in any way, shape or form- at all - but as said, the Algerian war finished in 1962... so very much in our lifetime- and for some, when our children were born. This is not ancient history OUR generation. This means the man whose head was severed could have served in the French army at the time. Not that that would excuse this dreadfuk, dreadful crime- at all.
The situation is quite different in the UK- but for North Africans in FRance, even those who are 2nd or 3rd generation born in France- equality of opportunities just do nto exist, and they are often put down all the time and treated like 2nd class citizens, possibly 3rd class (with white immigrants as 2nd)- have very menial jobs and the unemployment rate among the young is about 3 times for than for the 'white' French. VERY different to the UK situation.