> So much like we allow children time to learn in school before we expect them to compete in the job market, we should allow developing countries to employ protectionistic policies like tariffs, in order to protect and build up their fledgling industries nationally, before fully entering the world market in a couple decades when they are ready.

Let X be an industrialized country, and Y be the one exporting raw materials.

There are many tea plantations in Y. Companies from X own those plantations. They take the tea that is produced for some few cents, process it, put it in teabags, put the teabags in a well designed box, and then sell it across the world for a much higher value than whatever the cost of producing the plants was in Y. Most of the money goes to people in X.

Now what is we do what you say? then, companies from Y would be selling the boxed tea bags themselves. None of the money would go to X anymore. X exchanges its money for Y's tea.

In fact, X exchanges all of its money for other products from other countries as well. X now falls into a trade deficit.