Take it from an ice cream guy: If it's melted, it's ruined. That's why we have to stop global warming now. We've only got one atmosphere; we can't wait to take action until the damage is done and air pollution has forever changed our planet's delicate environmental balance. Earth Day reminds us that if we want to preserve our world for our kids and all the generations to come, the time to act is today. That is common sense, of course, but some politicians just don't seem to get it. Nonetheless, most of them love Earth Day, because it gives …