Wait, what?

Quite apart from the historic inaccuracies identified by Tim Worstall in this letter from a Dr Gavin Lewis in Manchester (I do rather wonder what doctorate that is), what the hell this is supposed to mean?

In Jamaica, David Cameron “spoke of his pride that Britain had played a part in abolishing the ‘abhorrent’ trade” and therefore ruled out reparations. However, taking pride in outlawing something that shouldn’t have started in the first place is hardly sufficient. No one for instance would try to get away with taking pride in having outlawed murder and therefore suggesting that no compensation for this crime need take place.

Really? If murder had been an entirely legal and accepted custom for all of human history, and then one nation unilaterally made it illegal, and spent an enormous amount of time and money trying to stamp it out, that wouldn't be something to be proud of?