Let me explain. Count me with the activists on the question of whether the United States should respond to the Syrian regime’s murder of some 1,400 civilians, more than 400 of them children, with poison gas. If there is no global response to this breaching of a universal taboo on using poison gas, the world will be a much more dangerous place. And only America can spearhead a credible response: Russia and China have rendered the United Nations Security Council meaningless; Europe is a military museum; the Arab League is worthless; all others are spectators. We are out front — alone. We may not want to be, but here we are. So we must lead.