By 2050, the bulk of the world's population growth will take place in Africa: of the additional 2.4 billion people projected between 2015 and 2050, 1.3 billion will be added in Africa, - ( 1.3 billion !!!!) 0.9 billion in Asia and only 0.2 billion in the rest of the world.
Given that within the continent of Africa, starvation is already so prevalent and with such an increase in population and without payment of heed to the theories of population growth of Thomas Malthus;
http://cgge.aag.org/PopulationandNaturalResources1e/CF_PopNatRes_Jan10/CF_PopNatRes_Jan108.html
Millions of starving peoples will head for the nearest food sources and Europe will be high on the list, unchecked, they will simply 'come and get us' in such numbers that the armed forces will be incapable of resisting them and we can then all starve together.