The sight of people who just last year called for intervention on one side of a civil war now calling for intervention on the other side puts in mind nothing so much as 1984. The world is divided into three great powers, Oceana, Eurasia, and East Asia that are in a constant state of war and shifting alliances. We see things from the perspective of Oceana (which includes England). Invariably Oceana is always allied with one of the Asian powers and at war with the other. (Whether Eurasia and East Asia ever join forces against Oceana is not addressed). Every few years, the alliances change and suddenly Oceana goes from being at war with Eurasia and allied with East Asia to being at war with East Asia and allied with Eurasia. Whenever that happens, all the back records have to be changed to deny the shifting alliance and make it appear that Oceana has always been at war with East Asia, and before long everyone (including most people who altered the records) starts believing it.
As recent events have shown, this is depressingly plausible. It was presumably inspired by the Nazi-Soviet Pact, when the Soviet Union went overnight from being allied with Nazi Germany against the Western Allies to being allied with the Western Allies against Nazi Germany. And, of course, the Pact came as a complete shock, since up until then the two countries had been mortal enemies.
The Battle of Blenheim, about the War of Spanish Succession in the early 18th Century. (Try reading an account of the war and see if you can straight all the Eurasia-East Asia moments).
Even in the Napoleonic Wars, when there were real ideological and social issues at stake, the frequency of shifting alliances is shocking. And, well, consider the Nazi-Soviet Pact.
In short, our current Eurasia-East Asia moment is not so extraordinary Quite the contrary, it is all to ordinary. But that doesn't mean that we have to let our leaders get away with it.