Afghanistan: As summit kicks off, NATO leaders talk tough on Russia, Islamic State --- NEWPORT, Wales — A summit of NATO leaders kicked off Thursday with tough talk about the threats from Russia and the Islamic State, but also questions about what action the alliance can take to counter growing challenges to Western security. -- The evolving stakes were clear. The military bloc and its allies must hammer out new strategies on multiple fronts — spanning from revived East-West political tensions to emerging dangers from well-armed and highly organized Islamist factions with strategic territory under their control. -- President Obama arrived at the summit after vowing to “degrade and destroy” the Islamic State militants and promising to protect the small Baltic states from any possible Russian aggression. -- Obama, Secretary of State John Kerry and European leaders then huddled privately with Ukraine’s president, Petro Poroshenko, even as Moscow reiterated its warnings that any moves by Ukraine to strengthen its ties with NATO could shatter fragile truce overtures in the country. -- Poroshenko said a cease-fire call could take effect Friday if agreements are reached during negotiations in Belarus that include representatives from Ukraine’s pro-Russian separatists. Yet clashes flared in parts of volatile eastern Ukraine as the summit began. -- The summit marks the largest gathering of foreign leaders on British soil: Leaders from 60 countries, including the 28 NATO members, the bloc’s partners and others. Russia was notable for its absence — the first time in years that Moscow has not been represented at a NATO summit and a sign of the deepening rifts between Moscow and its former Cold War foes. -- “The last NATO summit in the U.K., in 1990, took place at a pivotal moment” as the Soviet Union stumbled toward collapse, said Robin Niblett, director of the London-based think tank Chatham House.