Dr. Ron Medzon, an emergency room physician at Boston Medical Center, recalls treating victims injured in the bombing.
It’s the future face of Chinese industry: a high tech superpower employing tens of thousands of engineers rather than just poorly paid factory workers.
But the telecom giant Huawei, which makes much of the vital infrastructure underling mobile phone networks, is regarded with suspicion in the U.S.
It is seen as a pawn of the Chinese Communist Party, selling insecure equipment. American firms have been told they shouldn’t work with it.
The company says that’s unfair – and may be a result of anti-Chinese prejudice.
The BBC’s Rory Cellan-Jones reports from Huawei’s headquarters in Shenzhen.