Of a convicted and 100% guilty child murderer? I think a lot would have people are yes
They weren't children, they were teenage members of the ruling Socialist party youth wing. At least wait a few years before you try to rewrite this issue into a more politically correct version of history.
We are lucky we live in a politically reasonable and democratic country where unlike Ireland or Norway, there is little justification in committing a politically motivated killing of the controlling party.
If a Jew in 1930's Germany killed a bunch of Hitler Youth, then that would be the same principle. Such an act would have removed a number of future Nazis and with hindsight have had a tangible benefit. In that situation would you not have have praised that Jew for his act of mass murder?
Equally if someone had gone back in time and assassinated all of Sweden's current leadership, would Sweden now still be willingly participating in their own inevitable cultural genocide?
You can't always flatly condemn
political acts of violence without first being in the position to consider the historical outcome. Which in Breivik's case is still unclear.
Remember, the people who join Left wing political parties may one day have power over the lives of millions, it is the final act of social freedom to remove a political party by force if it doesn't properly represent the people. Hence America's gun laws (in theory)