Why doesn't America have a single payer healthcare system, is it that the big insurance companies are scared of the competition ?

The insurance companies lobby Congress not to pass a plan like that or they lose billions in business obviously. Every state has its own insurance commission to oversee business. Americans dont want the federal government telling people how to live and what to buy.

If we have single payer, the insurance companies will not have huge profits.

they're filthy rich bastards who value money over human life, and Trump supports those monsters

Because Corporations run the US.

Taxpayers are scared

If the US had Single Payer, it would put every insurance company out of business.

It would mean people could no longer profit on gambling which people die or not.

Less profitable.

yes they are