Beijing: Sirens wailed across China as the country came to a standstill Tuesday during a public memorial service for former leader Jiang Zemin, a tentative moment of unity after anti-lockdown protests shook the nation last week. Jiang, who died in Shanghai last Wednesday at the age of 96, oversaw a transformational era from the late 1980s into the new millennium. He took power in the aftermath of the 1989 Tiananmen Square crackdown and led China towards its emergence as a powerhouse on the global stage. A public memorial service began at 10:00 am (0200 GMT) Tuesday in Beijing’s Great Hall…