Whilst I dont want to defend the relatively low compensation for public-sector jobs in the UK, it is more nuanced than just salary.
In this case, it was actually a salary of £50,550 - £57,500, so total compensation of around £75k (circa $95k), as the pension scheme is in the order of 30% of your salary. Then there's the usual US vs UK medical cover and vacation allowances.
It's still a way off, but the gap is smaller than you think when you crunch all of the other benefits into a single number.
In this case, it was actually a salary of £50,550 - £57,500, so total compensation of around £75k (circa $95k), as the pension scheme is in the order of 30% of your salary. Then there's the usual US vs UK medical cover and vacation allowances.
It's still a way off, but the gap is smaller than you think when you crunch all of the other benefits into a single number.