It's been three and a half years since British combat troops left Afghanistan after fighting al-Qaeda and the Taliban for 13 years.

When they left they handed over responsibility for security to the Afghan army, with some British troops staying on to advise them.

But now BBC research suggests that the Taliban is openly active again in 70% of the country.

Alex Ford, an Afghanistan veteran who served there in 2011, said the withdrawal of troops was a political move.