Q&A: Who'd gain from a Trump border wall? Hint: Not Mexico

LOS ANGELES (AP) — As a billionaire developer, Donald Trump built casinos, luxe condo towers and lush golf courses. [...] as president, Trump aims to develop perhaps his most ambitious and surely his most contentious project yet: A wall along the nearly 2,000-mile U.S.-Mexico border. Ultimately, though, experts say the project, if built, could deliver a windfall for some large construction companies and their suppliers. Engineering and infrastructure companies that have worked on previous government projects could capture a chunk of the multibillion-dollar work. [...] the project would likely also be stymied by the struggles that have beset the industry in recent years, notably a shortage of skilled labor and rising materials costs. Some of the big companies include a subsidiary of the construction and engineering firm Parsons Corp. and Vulcan Materials Co., a producer of asphalt and ready-mixed concrete. The Trump administration has said it wants the wall to provide not only a physical barrier but also access roads, motorized vehicle gates, lighting, communication towers, ground sensors and remote video surveillance. Some that have expressed interest include Border Technology Inc. of Hereford, Arizona, whose website says it's worked with the Border Patrol using drones and other equipment to monitor the border. Along with engineering and design work, the project would require numerous construction and heavy machinery operators. Finding enough skilled laborers could be tough, though, because thousands of skilled construction workers left the industry after the housing meltdown and Great Recession a decade ago. The wall would also extend at least 6 feet underground to deter tunneling across the border; be resistant to climbing tools; and be strong enough to withstand attempts to make a 12-inch diameter breach in the wall using a sledgehammer, drill or other power tools. Given the estimated cost — some