A new poll shows for the first time that a majority of Americans support building a wall along the US-Mexico border — while three-fifths of the country sees illegal immigration under President Biden as a “very serious” problem. The Monmouth University survey released Monday found 53% of respondents favor building a border barrier while 46% say they are opposed. By contrast, 60% of Americans told the same pollster in September 2017, months after former President Donald Trump took office, that they were opposed to a border wall and just 35% said they were in favor of construction. When the question...