If you’re continually concerned about "existential threats," chances are that you are one in your own right. That is to say, if you say “We need to defeat/kill/eliminate so-and-so because if we don’t our nation/culture/way of life is in danger,” you’re the problem.
There are two reasons for that. One, even if you were able to do so, without a change in attitude you’ll simply start looking for another target. Two, such an attitude allows you to do or say anything against whatever you hate – and that includes lying and gossip.
In other words, your own character will be corroded.
Politicians understand this, which is why we had something like the Holocaust. We can talk about how horrible that was, and it was, but let’s not forget what led to it: Resentment toward some other, tough times and a certain nationalistic pride that became a defense of indefensible behavior.
And do you know what’s behind that? Fear, primarily of losing control or power.
For the last few decades we’re witnessed a lot of hand-wringing about the civility — or the lack thereof — in our political discourse. However, it’s the unrepentant absolutists, to whom compromise is akin to defeat, who create the problem in the first place — people who refuse to see things from another’s viewpoint or admit that they don’t have all the information.
None of this is to say that people aren’t allowed to hold ideological views. But if you’re not willing to adjust them in the face of new information, you have a real problem.