Chemicals are undoubtedly essential to life because our bodies are made out of chemicals.
Chemistry is the study of what substances are, how they behave, and how they interact. That broad but accurate definition basically includes everything made out of matter.
What's that leave out? Gravity, light, magnetism, the strong and weak nuclear forces, and, if you really want to stretch the point, the Higgs field.
Really, what the chemical industry means by "chemicals" is the set of substances with a high potential for misuse and harm. For example, methyl isocynate is an innocent but highly poisonous chemical that killed tens of thousands of sleeping people in Bhopal.
Chemicals don't kill people, people made out of chemicals kill people.
Of course, we'd be nowhere without pesticides, fungicides, fertilizers, pharmaceuticals, bullet-proof vests, gasoline, wood preservatives, explosives, paint, detergents, glass fiber, vinyl siding, chlorine, liquid absorbing diapers, aluminum foil, plastics, electronics, food preservatives, fireproofing, drain cleaners, buckyballs, synthetic fibers, and frozen dinners.
The problem is that some of these beneficial chemicals are destructive under certain circumstances.
So, yes, the chemical industry contributes greatly to modern life.
If only it hadn't left all those barrels of who-knows- what, who-knows-where, during all of those years before there were any stringent environmental laws.
That's when the suspicion started.