Putin, but cutting off the gas without any warning, only showed everyone that relying on Russia's gas so much was pure insanity in the first place. Now, Europe will pay the price for that stupidity. Hopefully, it won't be that high and things will come back to normal in a couple of years.
BTW, I wonder if US is paying attention. It's no longer 1940s when the US manufacturing output won WWII, now the US are mainly people sitting in offices, managing production that happens in China. What happens when the tensions between US and China get really serious? If China decides to cut off US's corporations from their manufacturing base, the US is just a bunch of people in offices sending slack messages to each other... That does not win wars.