I don’t think this has much to do with liberalism. howmany leftists, might be more politically correct for me to use neo-nazis as the example but whatever, have you talked to who say things like navalny is a nazi, all ukrainian troops are nazis, the free syrian army are isis, also isis is isis, israelis are nazis, kulaks were parasites, or the most classical one germans were nazis. just seems like people in general prefer to be against caricatures and comically evil people rather than humans
from my personal experience the need to collapse as you describe it stems moreso from the geopolitical position the societies of these liberal countries find themselves in moreso than the nature of their political ideology. it is in order to convince themselves of the need to continually take actions to protect their own interests and preferential position. I imagine it was probably pretty similar within nazi germany toward their opponents or within the soviet union against nazi germany. this is something I feel a lot of americans don’t exactly realize. anti-americanism is not as pervasive across the world as you may be led to believe and is definitely not at the same level of hate you’ll see with americans regarding china or other examples. this was especially weird to me when I first heard the song Eve of Destruction with the lyric “And think of all the hate there is in Red China” because the chinese really do not hate americans they just want to work together with them for mutual benefit. same sentiment was heard when putin gave his now famous interview with tucker carlson