Hasn't he heard of stricter UK border controls and isn't the defence of Europe down to NATO?
http://www.dailymail.co.uk/news/article-3456880/Even-leave-EU-won-t-able-control-immigration-David-Cameron-warns-Cabinet-ministers-say-PM-s-plan-UK-population-hit-80m.html
According to Cameron:
/// 'We're members of Nato, we're members of the UN, we're members of the IMF, I care about Britain being able to fix stuff – whether it's stopping pirates off the African coast, whether it's closing down illegal migration routes, closing down smugglers, whether it's standing up to Vladimir Putin with sanctions, whether it's the sanctions we put in place to get Iran to abandon its nuclear plan – having that seat in the EU, just as being a member of Nato is a vital way that we project our values, our power and our influence in the world.' ///
And the thought of him kow towing to the smaller East European states, (who we subsidise enormously) in trying to encourage them to accept smaller UK state benefit handouts, as got to be stomach wrenching.