The Bloomberg editorial board has a recent piece entitled "Free Trade Can Save the Rhino."  I was already aware of how free trade could lead to more competition and lower prices for consumers, but tell me more about saving the rhino:

Trade in endangered species is already heavily restricted by the U.S. The [Trans Pacific Partnership] deal would make it far more difficult for other countries to trade in trafficked items such as elephant tusks and rhino horns. The pact would, for the first time, integrate species conservation with trade access by requiring the 12 countries that sign it to adopt conservation laws, or live up to commitments they've already made yet routinely ignore.

...

Much of the demand for poached wildlife comes from the same countries negotiating the TPP. Vietnam, for example, is the main source of demand for rhino horn. Malaysia is an important shipping port with a low rate of wildlife-trafficking detection. Under the trade deal, both would have to change their see-no-evil attitude or risk trade sanctions.  ...

Ah, now I see.  It's not that free trade would do anything to save rhinos.  Rather, it's that the U.S. is a large and attractive market, and we can use our economic power to coerce our trading partners to adopt domestic policies that we like, including new conservation laws.  So actually, free trade has nothing to do with this.

The question of whether we should use our economic power to coerce our trading partners can be a difficult one.  I'm generally a skeptic on these sorts of things.  Here's something I said a while back in a more general international law context:

if we are going to try to change the world to be “more like us,” we need to think about how we want to change it ... If it is just more of the views of whichever party is currently in power, we may wear out our welcome with ever changing demands for how the world should behave.

But regardless of how we approach promoting our views around the world, we should not confuse this with free trade.