By invading Ukraine two weeks ago, President Vladmir Putin grossly overplayed his hand and inflicted a political disaster on Russia from which it will struggle to recover for decades.But are the US and Nato powers – over-confident because they sense that they are on the winning side – now making the same mistake by raising the stakes so high that the crisis is becoming less about Ukrainian independence and more about the survival of Putin and the future of the Russian state?The extent of the Russian failure in Ukraine since 24 February cannot be overstated. Putin has presided so far over one of the great fiascos in military history, and it is getting late in the day for him and his generals to reverse this.