THE 40th anniversary of the establishment of China-U.S.diplomatic relations should have made 2019 an important year for joint commemoration and renewed cooperation.Regrettably however,the U.S.has taken a series of actions to obstruct and suppress China in trade,science,and technology,and has been meddling in a series of issues concerning China’s territorial integrity and sovereignty.The U.S.actions not only undermined the mutual trust that the two sides built over four decades,but also swayed global stability and development.