What’s up with free trade in Colombia?

I have to admit that I really don’t understand the Colombian free trade deal that’s such a big deal these days. Sure, I get some of the broad strokes, but I haven’t read enough to know what the impact will be (and quite frankly, much of what I have read doesn’t really tell me anything).
But boy, in recent days, you’d almost think the Drug Czar was the Free Trade Czar.

• Statement from Director Walters on a Free Trade Agreement with Colombia
• Congress Should Move Forward With U.S.-Colombia Free Trade Agreement
• Susan Schwab on the Colombian Trade Deal

Clearly it’s contentious. Libertarians are for it (although it’s unclear to me if are allowed to oppose anything with the words “free trade” in the title regardless of what’s actually in there). Clinton advisor Mark Penn lost his job over it. Al Giordano seems to think that free trade is an attack on the U.S. by the Colombian government. thehim points to some good sources discussing human rights and the free trade agreement.
Free trade sounds good to me. On the other hand, I seriously doubt that it’s just about free trade — it’s certainly also about power and political advantage — and if the Drug Czar feels it’s important to promote, I’m immediately suspicious.
But, in reality, I have no clue.
So can anyone tell me what’s up with free trade?
(Specifically, if possible, as it relates to the drug war.)
Update: thehim finds an ironically amusing portion of the agreement:

1. Peru and Colombia shall recognize Bourbon Whiskey and Tennessee Whiskey, which is a straight Bourbon Whiskey authorized to be produced only in the State of Tennessee, as distinctive products of the United States. Accordingly, Peru and Colombia shall not permit the sale of any product as Bourbon Whiskey or Tennessee Whiskey, unless it has been manufactured in the United States in accordance with the laws and regulations of the United States governing the manufacture of Bourbon Whiskey and Tennessee Whiskey.