I’ve heard it many times from liberals who either mean the revolution would be more violent than our current system (it wouldn’t be), or suggesting that communists claim that we will achieve utopia if we’re just allowed to commit much brutality in the mean time (obviously false). This phrase annoys me so much, not just as a utilitarian, but also as someone who understands the meaning of words, as they are either suggesting that (in the moralistic sense) literally nothing is worth doing, ever, or that morality shouldn’t matter because everything is immoral anyway.
Absolutely, however it is there where the most care must be taken. A vast majority of the “body” can be rehabilitated, re-educated, and reintegrated, and any communist movement must try their best not to alienate the proletariat, even those that may have taken up arms against it in the past (Within reason of course). For example how the Chinese dealt with the Nationalist sympathizing south, Tibet, and Xinjiang. Reeducation and reintegration can be successful and must be attempted before harsher measures such as repression or crackdown.
So while all means may be justified, harsh measures with no real aim may backfire significantly.
For sure, the “necessary” in “any means necessary” is doing a lot of heavy lifting I think.