In the UK Forex trading can be structured as a bet. This is called 'spread betting.' This gets around capital gains tax and income tax in the UK as long as it's not your main source of income.

This wouldn't work in the US because gambling winnings are taxed even more highly than other sources of income.

Yes, I quite agree... indeed many States in America have Anti-Gambling Laws. In comparison, I was quite surprised at how ingrained in the culture gambling is in England and how it permeates through all levels of society. To me this seemed like quite the juxtaposition when you compare how the English vs Americans view new venture risk.

Not in this context. We're talking about the IRS. An American agency.