During WWII, no one debated the cost of beating fascism. Today we must cure the crisis of the biosphere at all costs.
These two pictures are not strictly analagous. The first shows bodies on the beaches of Normandy as a memorial of the cost of winning the Second World War. The second picture shows the cost of not winning the struggle to cure the crisis of the biosphere. If we do not act immediately to reverse the global heat spike, a fate something like the surface of Venus awaits the surface of the Earth, maybe within as short a time as a relatively few human generations.