Lebanon was on edge Monday after enraged protesters and world leaders alike demanded political reform following last week’s deadly explosion and waited to see if they would get it. Protesters took to the streets of Beirut again Sunday with video showing what appeared to be tear gas canisters being fired at demonstrators who had congregated in a street near the parliament. The scenes of public fury came as world leaders pledged millions in emergency aid to the country’s explosion-ravaged capital in a teleconference co-organized by France and the United Nations.