Yeah but what he really meant was 'backward'. Using that term would also have provoked all sorts of rage but it also might have invoked a discussion which resulted in something positive i.e. a recognition that taking people from countries where they sh1t in the road and treat women as cattle and putting them in western, secular, multi-cultural democracies creates all sorts of problems.
By using 'sh1thole' he just brought attention on himself with little chance of a constructive outcome.