Washington's stroke of "gentle diplomacy:US First Lady Michelle Obama today arrived in Beijing, embarking on a week-long charm offensive in China to infuse new thrust to sagging bilateral ties during which she will share the limelight with the country's First Lady, Peng Liyuan.50-year-old Michelle will team up with the wife of Chinese President Xi Jinping Peng Liyuan, who invited her American counterpart.Obama, a Harvard-educated lawyer, is expected to spend Friday with China's charismatic first lady, Peng Liyuan, who is admired at home as both a glamorous songstress and fashion icon.