Europe's first full-scale invasion of a sovereign state since World War II, a refugee crisis to match and an endgame sure to upend more than just the West's resolve: as the EU turns up the heat on Vladimir Putin, it's already asking citizens to turn down their thermostats. How will citizens react if on the one hand, Russia conquers Ukraine and on the other, the price of crude oil shoots past $200 a barrel? How to make do without Russian oil and gas?