London -- British-Indian prime ministerial candidate Rishi Sunak on Wednesday pledged a crackdown on Islamist extremism, the UK's most “significant terror threat”, with a widened government definition of extremism and strengthening existing terrorism legislation. The 42-year-old former Chancellor, who is seen closing the gap with opponent Foreign Secretary Liz Truss in the race to 10 Downing Street, also vowed to weed out organisations that promote extremism in the UK and refocus the “failing”. Prevent programme, a government tool intended to tackle Islamist extremism. “There is no more important duty for a Prime Minister than keeping our country and our people...