Last week the minimum wage for workers aged 18-20 rose further, which the BBC reported as millions of people ‘getting a pay rise’. Maybe, but Britain’s youth unemployment rate has become Europe’s worst and teenagers have been especially frozen out of the jobs market, likely also a second-order effect of increases in low-skilled immigration. The minimum wage policy could prove consequential because London now has youth unemployment rates of 25 per cent, and previous high water marks - 1980/1 and 2010/1 - led to urban disorder. In the same week, a Labour MP and former shadow cabinet minister proposed benefits for migrant workers who have higher rates of relative poverty, a policy that would likely increase poverty within Britain by incentivising low-skilled workers to settle here. The most obvious example of second-order effects is rent control, which consistently reduces the supply of housing, but that’s not preventing the Scottish government from going ahead with the idea. This is despite the policy in Edinb…