For months now, the US has been destroying boats in the Caribbean it accuses of smuggling drugs into its country.

Now it has brought the world's largest warship to within striking distance of Venezeula. It accuses its leader Nicolas Maduro of running a narco-terrorist organisation aimed at destabilising the US through drugs.

But with cocaine from the country reportedly accounting for just 10% of the US market - what part are the country's rich oil reserves and the US's own politics playing in his motives?

Will Tullis tells Daniel Hewitt what you need to know.