Here's Why Russia Is Really Invading Ukraine & Why It Hasn't Triggered A World War

After weeks of hinting at possibly invading Ukraine and building up troops at the border, Russia has finally made its move.

Russian President Vladimir Putin attacked Ukraine by air, sea and land on Thursday, prompting world leaders to call him out and condemn him, especially after he tried to claim that he was doing it to defend Russia.

Meanwhile, Ukraine has been left to fight its own losing battle against Russia's invasion force of 190,000 troops.

Putin claimed he had to invade Ukraine to protect the Russian and Ukrainian people from so-called "extremists," whom he blames for forcing out Ukraine's pro-Russian president in 2014.

During a speech ahead of the attack, Putin even went so far as to say that his actions are to protect pro-Russian separatists from genocide, hence why he's hoping for the "demilitarization and de-Nazification" of the country.

However, those claims have been rendered bogus given that there has been no documented genocide going on in Ukraine, reported the BBC.

But the deeper reason Putin is moving into Ukraine has a lot to do with shared history.

Ukraine was once part of the Soviet Union, and Putin has made it clear over the years that letting Ukraine become its own country was a mistake. Now he's trying to address that mistake, as he said in his pre-invasion speech.

Putin has also said that he never wants to see Ukraine join NATO, which he sees as "obviously anti-Russian."

Back in 2008, when the idea of Ukraine joining NATO was first brought up, Putin made his opposition very obvious and even said that doing such a thing would be "a hostile act towards Russia."

Ukraine has been trying to join NATO and align itself with the European Union for years, but NATO nations have also been reluctant to let it into the club.

That's because NATO is based on a simple idea: if you attack one of us, you attack all of us.

If Ukraine were part of NATO today, all the other NATO members — including the U.S. and Canada — would have to jump in and defend it from Russia. Suddenly you'd have nuclear-armed powers fighting each other, and the chance of a World War III involving nukes is on the table.

That's why world leaders are promising things like sanctions instead of combat. They don't want Ukraine to be taken over, but they really don't want to get into a world war.

And they really, really don't want to see a nuclear weapon go off.