When people trade free from government interference. Did you honestly not know or understand this?
Free Trade is the condition of trade between Georgia and Florida, or Florida and Alaska. There are no quotas, duties, tariffs, etc.
Even there, from state to state, its not an absence of government interference.
True there are no tarriffs, but what really defines it is equal protection under the law thus creating and maintaining a true market driven economy.
If there were no government intervention Microsoft would have never been sued, Standard Oil wouldn't have been broken up, and the telephone company wouldn't have been chopped into pieces.
The game doesn't start and stop with a discussion on tarriffs. Free Trade in its true form is a combination of many things. In fact, there are many things that we import right now from various countries that have zero tarriffs on them at our ports. Yet its not at all a Free Trade Agreement.
Note that those states operate under a common national government. That is why it works, and also why international free trade requires you to give up sovereignty to governing bodies like the WTO.
Before you say it, yes. Free Trade is government engineered.
It is not some centrally planned, micro managed communist system. It is however an engineered set of common laws employed to create an environment. It is not some liberatarian idea.
It is a basic set of rules, just like football has, then everyone has to abide in those rules and compete as they will.
Making a rule book of common rules is not micromanaging the football team. Likewise, Liberatarian views and philosophies on trade are not in touch with reality.