Actually there was an unsuccessful coup years earlier in 2004 when Putin, without any provocation or even a vague justification, tried to assassinate Yuschenko. He wanted Yanukovych to win an uncontested election.
For comparison, imagine Chicom putting a nerve agent in GHW Bush’s tea to give Clinton a free run at the White House. Who here wouldn’t have considered it an act of War.
Then in 2008 Russia invaded Georgia and Poland warned Ukraine that the blueprint was being developed to invade Ukraine afterwards on similar lines.
Then in 2013 Putin attempted yet another colour revolution in Ukraine, first by blackmailing Azarov and Yanukovych into delaying the EU trade negotiations (overwhelmingly approved by the Rada as well as the overall citizenship of Ukraine) while flooding the Donbas with “settlers” and “separatists”.
And in December 2013, Yanukovych signed a “deal” with Russia instead without discussing it with anyone in the Rada. This “deal” put Russia effectively in charge of Ukraine’s finances and opened the door for Russia to pull the plug on Ukrainian independence.
Maidan wasn’t a coup by Ukraine. It was a Ukrainian watershed reaction to a coup instigated by Putin and enabled by Yanukovych.
Three times Russia had attempted a hostile takeover of Ukraine without any provocation. The third time was the final straw, Ukraine retaliated.
I put the word coup in quotes for a reason. It wasn’t a coup.