The key insight of Adam Smith's Wealth of Nations is misleadingly simple: if an exchange between two parties is voluntary, it will not take place unl… - Milton Friedman

Adam Smith’s key insight was that both parties to an exchange can benefit and that, so long as cooperation is strictly voluntary, no exchange will take place unless both parties do benefit.

In the course of General Westmoreland's testimony, he made the statement that he did not want to command an army of mercenaries. I stopped him and said, 'General, would you rather command an army of slaves?' He drew himself up and said, 'I don't like to hear our patriotic draftees referred to as slaves.' I replied, 'I don't like to hear our patriotic volunteers referred to as mercenaries.' But I went on to say, 'If they are mercenaries, then I, sir, am a mercenary professor, and you, sir, are a mercenary general; we are served by mercenary physicians, we use a mercenary lawyer, and we get our meat from a mercenary butcher.' That was the last that we heard from the general about mercenaries.

A military draft is undesirable and unnecessary. We can and should man our armed forces with volunteers—as the United States has traditionally done except in major wars.

Let us not underestimate the ingenuity of the poor people in converting what they get from the relief worker to what they want. And that’s just wasteful. They would be far better off if we just gave them the money and let them spend it.