Probably not. It was probably just the Chinese lack of Occupational Health and Safety. Probably explosives meant for fireworks. Which is a pity, cause I love a good conspiracy theory. But not everything is secret squirrel business.

The big explosion is the second of 2-3. I can picture some fool planning a small scam, with dropping prices, and getting more bang for his buck than expected.

It certainly would help the local Chinese economy short term -- construction, labor, etc. Realistically? No. China doesn't need to level buildings; just kick the currency down a couple of percentage points, buy cheap American stock and wait for a good rally.

Could have been the USA taking the cyber war to the real world as the "National Supercomputing Center of Tianjin " thought to be totally decimated in August 12 China cargo explosion." http://i.imgur.com/GIaoC8u.jpg

More likely in my opinion that a foreign government wanted to cause a major disaster as a "back off" measure about China's actions in the South China Sea. Japan is definitely threatened by the live-fire drills the Chinese are running out there; they've openly admitted as much.