[user104658]

The increased crime rates are in (large) part due the ghettoism which, yes, has links to immigration (deprived areas in London tend to have large immigrant populations) but the problem is the social division and isolation caused BY ghettoism... the problem is "not enough integration", not "too much immigration".

Also a major factor in London's crime rates being higher than New York is that New York's violent crime rates have fallen by almost 20% since the de facto handgun ban.

More importantly; you're comparing the UK's MOST problematic cities with a cherrypicked US couterpart; The US has four cities (St. Louis, Baltimore, New Orleans and Detroit) in the top 50 for murder worldwide. The UK has zero. Also... take a look at those four US cities that are in the top 50. What do they have problems with? Immigration? No; the cities with the highest immigrant population in the US are generally California or Miami based. Also, New York is in the top 10 for immigration.

So what DO those violent US cities all have in common? What DO they have in common with London? Large areas with social and economic deprivation and increasing ghettoism.