Democratic presidential nominee Kamala Harris has picked Minnesota Governor Tim Walz to be her vice presidential running mate in the race for the White House. With three months to go until the US presidential election, this is Harris’ first major decision since becoming her centre-left party’s candidate to go up against former Republican president Donald Trump. “I am proud to announce that I’ve asked Tim Walz to be my running mate,” Harris posted on social media. “As a governor, a coach, a teacher, and a veteran, he’s delivered for working families like his. It’s great to have him on the team….