By Norman Bordadora Philippine Daily Inquirer CAGAYAN DE ORO CITY—President Benigno Aquino III on Tuesday declared a state of national calamity and vowed to mobilize assistance for victims of the worst storm to hit his presidency. “I need to ask myself. Did the government do enough to prevent this kind of a tragedy? I don’t think I can accept that we have done everything,” Mr. Aquino told evacuees at Cagayan de Oro Central School during a lightning visit to the disaster zone four days after Tropical Storm “Sendong” struck. “I know we could have done more.” The President himself has been criticized for attending a Christmas Party for his Presidential Security Group on Saturday as Sendong rampaged across Mindanao and the Visayas, igniting flash floods and causing death and destruction. “My concern right now is specifically those missing,” Mr. Aquino said. “Let us exhaust all possible means to try and find all of these missing individuals,” he told national an...