This month, the world has been horrified to witness the Russian invasion of Ukraine.

The courage of Ukrainian fighters and the suffering of the Ukrainian people have brought millions out into the streets to demonstrate against the Russian attack.

It's a tragedy of epic proportions. It could ultimately exceed the pain of the Holodomor, when Soviet agricultural policies led to mass starvation in Ukraine in 1932 and 1933.

Is it any wonder that people are calling Russian president Vladimir Putin a "war criminal" for invading an independent country?

But what are the roots of Putin's war of aggression against his neighbour on February 24?

Just nine days earlier, King's College's politics department posted a videotaped presentation on YouTube by University of Chicago political scientist John J. Mearsheimer. In it, he pointed the finger directly at the West.

"The interview was recorded Tuesday 15th February before Russia invaded Ukraine," King's Politics states on YouTube.

Mearsheimer, a West Point graduate, served five years as an officer in the U.S. Air Force before going to graduate school.

"The United States and its allies are responsible for this crisis, not Putin and Russia," Mearsheimer said in the video below. "Now why do I say that? It’s very important to understand is what the West has been trying to do since 2008 is turn Ukraine into a western bulwark on Russia’s border.

"That policy had three dimensions to it," he continued. "The first and most important is NATO expansion. The idea was that we were going to expand NATO eastward to include Ukraine. The second element of the strategy was EU expansion. So in other words, it was not just NATO expansion that was going to go and include Ukraine, it was also EU expansion.

"And the third element of the strategy was the colour revolution," he added. "In the case of Ukraine, that was the Orange Revolution. And the idea was to turn Ukraine into a liberal democracy like Britain, like the United States. And not only a liberal democracy but a liberal democracy that was allied with the United States. Because again, this is all part and parcel of a strategy that is designed to make Ukraine a western bulwark on Russia’s border.”

https://twitter.com/Denys_Shmyhal/status/1498341178567180294

Mearsheimer pointed out that there were two major expansions of NATO leading up to an April 2008 summit in Bucharest.

Back in 1999, Poland, Hungary, and the Czech Republic were admitted into the military alliance. Then in 2004, Romania, Bulgaria, Slovakia, Slovenia, and the Baltic states were added.

According to Mearsheimer, the Russians "swallowed them", even though they didn't like these developments.

In Bucharest in 2008, he stated, NATO announced that Georgia and Ukraine would also become part of the alliance. And the Russians made it clear that this wouldn't happen, drawing a line in the sand.

In August 2008, the Russians invaded Georgia. Then on February 22, 2014, a crisis broke out over Ukraine.

"And it was mainly precipitated by a coup in Ukraine that overthrew a pro-Russian leader and installed a pro-American leader," Mearsheimer said.

He maintained that the Americans were involved and that the Russians went ballistic. (Others have called the replacement of pro-Russia leader Viktor Yanukovych the "Revolution of Dignity" or the "Maidan Revolution" rather than a coup.)

Then, two things happened that same year.

First, the Russians seized Crimea from Ukraine, mainly to keep the important military base in Sevastopol, according to Mearsheimer. Then, he said, the Russians took advantage of a civil war in Ukraine by ensuring that their allies in the eastern areas would not be defeated by Ukrainian forces.

"The Russians are basically saying we will wreck Ukraine before we allow Ukraine to become a member of NATO," Mearsheimer said.

He emphasized that the Obama administration did not arm the Ukrainian government, but that changed in recent years. That upped the ante for the Russians.

Mearsheimer said that the Russians were also "spooked" when the Turks provided the Ukrainian government with drones.

Even though Ukraine is still not a member of NATO, he noted that it has become a western ally armed by the West. Through this, Ukraine is becoming a "de facto member" of NATO.

And for Russia, he said, it's an "existential threat" for Ukraine to be part of NATO. This year, the situation reached a boiling point, he added.

"The United States views the Western Hemisphere as its backyard and it prohibits distant great powers from coming into its backyard," Mearsheimer said in the video. "Well, don’t you think the Russians are going to be deeply disturbed by the United States turning Ukraine into a bulwark right on its borders? Of course they are.

"And the Russians told us that immediately after the Bucharest summit," he continued. "The Russians made it categorically clear, categorically clear, that Ukraine is not going to become part of NATO. But of course, the Americans and their allies did not listen because we believe that we’re the good guys. We’re a benign hegemon here in the United States and we can do pretty much anything we want in the world. And for a while, it looked like we could get away with that.”

On February 15, Mearsheimer said that the Russians are not interested in negotiating anymore over Ukraine.

"They're interested in altering the status quo," he declared.