No, Russia should not have invaded Ukraine despite its reneging on the Minsk Agreement and its reaching out to join the EU and NATO.
Neither should the US have invaded Iraq, threatened Iran and Venezuela, boycotted Cuba, and helped assassinate Allende in Chile. Not to mention the CIA training Ukrainian forces for the past six to eight years.
But that's what powerful nations do when they can get away with it, which they often do thanks largely to the media shaping public opinion. When the other side does it we call it propaganda in an unfree nation; when we do it it's called the free press of the free world.