The US government has revoked the visas of at least 50 politicians and government officials in Mexico amid the Trump administration's crackdown on drug cartels and their suspected political allies, two Mexican officials told Reuters. A handful of these cases have been publicised, but Reuters reporting shows the visa cancellations are far more widespread than previously reported. According to three former US ambassadors, previous administrations have revoked visas in this way - but not to the same degree, which they said was indicative of President Donald Trump's willingness to use the diplomatic tool to achieve policy goals. "The Trump administration is finding new ways to exert more pressure on Mexico," said Tony Wayne, US ambassador to Mexico from 2011 to...