What is coming out of the woodwork here is that successive governments including Merkel were warned of Putin's increasingly unveiled intentions regarding the Ukraine and simply disregarded them, preferring trade and making money. Similar to the greed of the City of London. Desire for money really is the root of all sorts of evil.
I recently saw footage of Trump in 2018 warning the Germans in no uncertain terms they were getting completely dependent on Russian energy supplies, and in the background you could see the foreign minister Maas and his team laughing at this. Well, to coin a phrase, they aren't laughing now.