Two historical myths. 

The first is that autocrats by their nature desire conquest and the expansion of their empires. “We have also seen many times in history,” the U.S. ambassador to NATO said, “where if a dictator is not stopped, or an authoritarian leader, they keep going.”

Inconveniently, this axiom is not borne out by history. Nor does the U.S. apply it to several of its contemporary friends; Washington does not assume that the autocratic rulers of Saudi Arabia or Egypt are bent on conquering the Middle East or Africa.

The second is that Putin has said as much. Putin is often quoted as saying that “people in Russia say that those who do not regret the collapse of the Soviet Union have no heart.” The second part of his statement is quoted less often: “And those that do regret it have no brain.” The historical record shows that, in his over two decades in power, Putin has not “kept going.” When Russian forces have been deployed, they have been limited to specific objectives when they could have easily kept going, as in Georgia in 2008 and Ukraine in 2014, when military conquest could have been accomplished with ease. If Putin went to war in Ukraine to prevent a war with NATO, then it makes little sense that he would use the war in Ukraine as a means to start a war with NATO. 

https://www.theamericanconservative.com/is-putin-bent-on-conquering-europe/