But Megan McArdle is more than likely going to say this is wrong:

EU trade commissioner Peter Mandelson has a tough couple of months ahead. He's determined to create a set of new trade deals between the EU and countries that are mostly former colonies, known in trade-speak as the African, Caribbean and Pacific (ACP) economies. His main problem is the huge opposition being stirred up by the usual suspects in the development community such as ActionAid and the World Development Movement. They do not like Mr Mandelson's insistence that the ACP countries must reciprocate in some way.
...
They say that poor countries have difficulties collecting ordinary taxes and that tariffs are an easy way to pay for hospitals and roads. Mr Mandelson isn't having any of this. Speaking to the European Parliament's Development Committee yesterday, he said: "the evidence is that when tariffs come down, tariff revenue tends to go up."

Now if Congress would only get that message too.  Via Samizdata.  And for those of you who need a refresher on Voodoo Economics, you might want to watch this: