EAST-WEST AGAIN: The U.S. and China began to re-engage Tuesday on knotty issues ranging from economic frictions to North Korea's nuclear program following a months-long hiatus during President Barack Obama's re-election and China's installation of new leaders.

EMISSARY: Chinese President Xi Jinping met with visiting U.S. Treasury Secretary Jacob Lew in the first high-level exchange between the sides in six months and the start of a series of meetings that will test the potential for cooperation between the world's first- and second-largest economies.

MUTUAL SUSPICION: The meeting takes place amid great misgivings in Beijing over Washington's renewed focus on the Asia-Pacific region and Washington's concerns over China's reluctance to pressure its mercurial ally North Korea and Beijing's alleged state-sponsored computer hacking.