On Tuesday evening, as 12 Democratic presidential hopefuls debated policy ideas about healthcare, gun control measures, and protecting reproductive rights, President Donald Trump once again vetoed legislation that would end his declaration of a national emergency at the southern border and prevent him from building his wall. It’s the sixth veto of Trump’s presidency and comes seven months after he first vetoed a similar measure in March, which had been passed by the Senate in a 59-41 vote, with twelve Republicans siding with Democrats.