In 2005, Vladimir Putin told Russians that the fall of the Soviet Union was the “greatest geo-political catastrophe of the century.” “As for the Russian people, it became a genuine tragedy. Tens of millions of our fellow citizens and countrymen found themselves beyond the fringes of Russian territory.” The North Atlantic Treaty Organization (NATO) had advanced eastward relentlessly, first admitting the former “captive nations” of the Warsaw Pact, then admitting the three Baltic states which had long been under Russian rule. The United States had used its power to overthrow the governments of Iraq (2003) and Libya (2011) and to call for the overthrow of the government of Syria (2011). Then the Americans left those places in blazing ruins. For more than twenty years he labored to undo that “catastrophe.” His accomplishments are not petty.
He rose from a low-level KGB officer to be the dictator of Russia, regardless of varying formal titles. He brought to heel the oligarchs who had “spontaneously privatized” much of Soviet-era industry to their own advantage. He checked the further disintegration of the Russian Federation by a savage war in Chechnya.
Since he came to power, Putin has been advancing the pre-existing Eurasian Economic Union. This EEU is intended to rival the European Community (EC) and to pull together the economies of Russia and other former Soviet states. Anyone who has read the history of Nineteenth Century German unification or the history of the development of the EC knows that “butter” comes before “gun” in the dictionary. In this effort, Ukraine figured as a rich prize.
He turned to trying to regain a measure of control over the countries that had left the Soviet Union in the wake of its collapse. In 2008 he sent Russian troops into the former Soviet republic of Georgia.
Since the 2011 “Arab Spring” he has opposed the Americans with direct military aid in the Syrian and Libyan civil wars. In both cases, Russia’s clients are winning.
In 2014, after his attempt to lure Ukraine into the EEU foundered, he sent Russian troops into Crimea and the Donbas in eastern Ukraine.
He has achieved a measure of success in cozening Turkey, Hungary, and Italy. Each has its own discontents with the European Union or NATO or the United States. Then there’s China.
The United States and its presidents have been going through a bad patch since the end of the Cold War. Vladimir Putin seems to be a bad man in a hurry. That doesn’t mean he will win.
 On the Cold War-era term, see: https://en.wikipedia.org/wiki/Captive_Nations#:~:text=%22Captive%20Nations%22%20is%20a%20term,Communist%20administration%2C%20primarily%20Soviet%20rule. On the more broadly applicable “puppet state,” see: https://en.wikipedia.org/wiki/Puppet_state
 It speaks volumes to the mentality of the Obama Administration foreign policy officials (and of the president himself) that they were unable to distinguish between form and substance. Dmitri Medvedev went where Putin sent him and did what Putin told him.
 Wikipedia is as accessible as anything else on this fight. See: https://en.wikipedia.org/wiki/First_Chechen_War and https://en.wikipedia.org/wiki/Second_Chechen_War. For an argument that Putin himself staged the bombing of apartment buildings to justify the second war, see: https://en.wikipedia.org/wiki/Russian_apartment_bombings