The Iranian government on Monday stepped up military threats in advance of an anniversary celebration as major powers continued talks on a new round of sanctions. Iran's supreme leader, Ayatollah Ali Khamenei, said in Tehran that his country would stun the Western world on Thursday, the 31st anniversary of Iran's Islamic revolution. Iran's defense minister announced on Monday that its forces had conducted successful tests on new armed unmanned aircraft and advanced air defenses. "The Iranian nation, with its unity and God's grace, will punch the arrogance [Western powers] on the 22nd of Bahman [Feb. 11] in a way that...