By “prolong the war” you actually mean “defend their borders” but cool

No, in fact I do mean "prolong the war". Defending the borders is prolonging the war. The only act that is not prolonging the war is ending the war. You can't euphemize it.

Edit to add: Not sure why you bring up Crimea, if over 95% of the votes are to return to Russian control in a referendum, how can you imply it was not an act of "goodwill and trustworthiness".

If you want to talk about being untrustworthy, acting without goodwill, and outright deceitfulness, you'd need to simply realize that a USA-backed coup in 2014 caused problems, and now the USA is somehow supposed to be seen as acting with goodwill here. It should be transparent the motives of the USA, especially to those it doesn't care that die in its proxy war.