[most people read the msm for history and do not realize Crimea has been russian for hundreds of years. The people voted overwhelmly to rejoin russia.]
And the Sudetenland had been German for hundreds of years. So what? The principal significance of the Crimea to Ukraine is that it prevents Russia from controlling both sides of the Kerch Strait. The Kerch Strait controls access to over half of Ukraine’s coastline, and all of its major ports. Whereas Russia has plenty of other ports in the Black Sea. In the long run, Ukraine will need to rebuild its ports in a locale less vulnerable to Russian attack. But ports don’t build themselves and cost a lot of money. And a good chunk of Ukrainian industry is located near its existing ports. That will also have to be moved.