Quick question. Why is it such an awful thing that America have pulled out of this deal?

Lets assume for one crazy moment that any pledges America made in signing this deal are still going to happen and that they aren't going to start an Eiffel Tower sized coal fire in the rain forest in celebration.

What difference does it make?

As an aside. It really fills me with embarrassment as an English man when I hear English commentary on all things Trump. It doesnt matter if its here, in the office or on the news, I find it unbearably arrogant. I genuinely dont know where we as a people get the stones to snigger over our tea and toast given that we're doing such a great job of running our country.