Look, it is suicide to launch one. Even the craziest shitheads like the Taliban and North Korea won’t do it. Even though some of these people are on the darker side of human nature, the dark side still has a self preservation aspect, doubly so for those who like to keep power.
Russia killing Ukrainians to secure Ukraine is still somewhat in line with other invasions of this and last century. We are not yet in madness territory, not by any stretch.
Most likely we won’t even hit the civilian casualty numbers of the Iraq/Afghanistan war.