Separate topic altogether. The question is whether the current lack of fighting means the Ukrainians are rolling over for the Russian invaders. If you look at Gulf War I, it's clear that planning, mobilization and staging, even for the US, took over 5 months. The Ukrainians will take weeks or months to get ready. The calm today may be the calm before the storm to come.
A home owner will not draw on a home invader who has the drop on him. Once the perp turns his back, the home owner may fetch the pistol he has hidden and start blazing away.
This wasn’t a hostile invasion, this was more like sending in reinforcements and protection. Crimea doesn’t agree with the ousting of the president, or with the idea of aligning with the EU. They want to stay right where they are, in the arms of the Russians. They just passed a resolution the other day saying as much to make sure the world knows that.
Invasions are by definition hostile. Mexico could move into a near-majority Hispanic border state like CA or NM, say it is moving in to protect Hispanics from gringo violence and disarm Federal troops and local police without firing a shot. No one would dispute that this was a hostile act against the US.
Hitler's annexation of the Sudetenland was accomplished not only without any violence - it was done so with the express approval of the Allied Powers. When the war was over, most Germans were expelled from Czechoslovakia, with the exception of those who had proved their loyalty, via acts of resistance against the Third Reich. Crimeans who side with Russia had better be sure the Russians will win. If the Ukrainians get it back, the Crimeans most prominent in siding with the Russians will face the fate of the Tories who sided with Britain against the Patriots during the American Revolution - expulsion.