Going to war over spheres of influence.  The 21st century is going to be just as rough as the 20th century.

“Russia says, for instance, that it is threatened by Nato expanding eastwards and potentially including Ukraine as a member. The response of the Nato powers is to say that its door should remain open to all and, more privately, that Ukraine is unlikely to join the organisation in the foreseeable future, so why is Moscow objecting so strongly?

But there is a perfectly rational Russian response to this, which is to point to the furious American response to Soviet missiles being based in Cuba that almost led to a nuclear war in 1962. The Russians can also reasonably ask why, if Ukraine’s Nato membership is such a distant prospect, Nato powers are so insistent on keeping open the option, even though, by doing so, they increase the chances of a shooting war.”

The Russian national interest must be preserved I suppose, and that is reason enough to initiate an armed conflict.  We watch the US do it all the time as well, just that somehow we’re the good guys.

With resources scarce, this model of armed intervention will occur more often.  We’ll have to get used to it or be prepared to radically reorganize our societies around the idea that we as co-inhabitants on this earth all have the right to live in peace.