Behind intolerance hides the most primal sense of ego, a clandestine belief that “I and my kind are the only thing that should be.”
People may give reasons for their intolerance, but the reasons are secondary. They despise others for the space they consume. Stripped to the bone, it is senseless hatred without reason.
It is the core of all evil. It is what holds the human soul in exile from the garden.
And its only cure is in unbridled acts of kindness, in opening your heart to the other guy regardless of how different and distant the other guy may be.
Caring beyond reason.

You cannot preach "love everyone". That forgets what Amalek did. And it forgets what the Nazis did.
And it forgets the various governments including the USA which brought "former" Nazis on board or connected them as assets.
Nay, I also do not believe 'love everyone' is proper. We do need to note though, that in the vision of the third Temple, there is a place for the offerings of Non-Jewish nations. I would never say to forget, in fact we are told not to. But, it is followed up by HaShem Himself, acting out retribution on those that have wronged you.