china: poisonous toys, poisonous milk, too young athlete?

Tweet

with the enumeration i did above is china making fun of the rest of the world? why do they use lead to paint the toys they export, why do they use chemicals that harm children just to preserve powdered milk longer, why do they enter too young an athlete in the olympics that they flawlessly hosted? and why is china, in spite of these and many unmentioned shameful others, still a force to be respected?