And that is at it should be.
A few dozen nuclear detonations at the right altitude and we can. And without too much effort. With cars? Maybe that will take a bit more work 
I don't think that you should be as confident in that statement as you apparently are. It's unlikely we can hurt the planet with cars. But it's not impossible.
I think that's a silly argument for a couple of reasons: first, unlike all other forms of life that we are aware of at this time, we are in a unique situation to shape our own future and our own destiny and avoid the inevitable wipe out that's right around the corner. Second, even if we ignore the first point, it would be silly for us to hasten to terminate our collective existence just because it is bound to terminate at some point.
I don't buy the "in the long run we'll all be dead" type of arguments. Even if that's the case, there's something to be said about our quality of life today when we're alive and not dead. Under the mentality you advocate, perhaps we should turn Yellowstone into a garbage dump. Sure, we could enjoy the pristine nature now, but why? After all, what's the point? It's going to end someday too...
Oh Im certainly not advocating that we should all take my position, more that I just cant bring myself to care. Thats all. Lol.
Your reasoning is certainly more logical than mine on this point.
