President Trump appeared this morning in front of a gathering of the United Nations General Assembly and went on the attack. “Your countries are going to hell.”Trump spent roughly a quarter of his address railing against concerns about global warming. He claimed the scientific consensus on the issue was “made by stupid people,” and described climate change as the “greatest con job” ever perpetrated on the world. The president also accused environmentalists of wanting to “kill all the cows.”Trump also aired other grievances, often veering off script. He questioned whether the U.N. should exist; he attacked leaders who recognized a Palestinian state; he insulted London’s mayor; and he complained about windmills ruining beautiful landscapes.