Ha-Joon Chang has always struck me as a Johnny One Note as he has basically recycled the same idea over and over again in book after book, article after article, and presentation after presentation. Essentially, Chang gives a modern spin on Friedrich List's idea that, having ascended to the top of the ladder in the global political economy via the use of tariffs, subsidies, and other supports, industrialized nations are keen on "kicking away the ladder" by promoting the concept of free trade asking developing countries that haven't reached a similar stage of development to play by rules that disallow the use of such supports. Since the ladder has already been kicked away, they obviously can't progress to a similar level of development--or so he says.
If you haven't come across Ha-Joon Chang before, I suggest two resources in addition to the clip above. First, don't miss a recent debate in the pages of Development Policy Review between Chang and current World Bank Chief Economist Justin Lin. Although I generally believe the latter came out well ahead, you can read for yourselves. Next, he also made a presentation here at the LSE recently. There is a podcast of the event available as well as a video clip.
I found the above clip from Oxfam while searching for something else. In it, Chang makes the suggestion that championing free trade for LDCs for their betterment is like asking your child to go out in the world to fend for himself or herself before maturing. Yes, it's the "infant industry" argument all over again. However, the framing is ever-so-slightly novel as far as Chang goes, so play it and see for yourselves.