It was foolish. The British press on both the left (including the Independent, rhough this cartoon and editorials), and on the right have both rightly attacked him for it.
Frankly, with such media support as well as support for Pakistan that is coming from prominent politicians, it should be easy for Zardari to get Cameron to issue a clear statement in London that Pakistan does not export terror.
If Zardari fails to do so, it will be further evidence of his utter incompetence.