Vietnam, one of the world’s five remaining Communist states, is about to get new leadership. The biggest moves will emerge from a secretive, twice-a-decade meeting — the National Party Congress — which started Jan. 25 in Hanoi and ends Feb. 2. From general secretary on down, there’ll be a shakeup of the characters who will steer the Southeast Asian nation of 97.6 million people through a period of tense relations involving China and the U.S. While no major policy reset is anticipated, the cong