In response to North Korea’s latest nuclear test, South Korea on Thursday announced it would resume cross-border propaganda broadcasts that Pyongyang considers an act of war. Seoul also began talks with Washington that could see the arrival of nuclear-powered U.S. submarines and warplanes to the Korean Peninsula. From Seoul to Washington, Beijing to the United Nations, world powers are looking at ways to punish Pyongyang for the test of what it called a new and powerful hydrogen bomb. The loudspeaker broadcasts, which will start Friday, believed to be the birthday of young North Korean leader Kim Jong Un, are certain to infuriate authoritarian Pyongyang because they are meant to raise questions in North Korean minds about the infallibility of the ruling Kim family. South Korea stopped earlier broadcasts after it agreed with Pyongyang in late August on a package of measures aimed at easing animosities that had the rivals threatening war. WORLD LEADERS BLAST KIM JONG UN REGIME AFTER H-BOMB REPORTS Experts, meanwhile, are trying to uncover more details about the detonation that drew worldwide skepticism and condemnation. It may take weeks or longer to confirm or refute the North’s claim that it successfully tested a hydrogen bomb, which would…