Blue Poppy/Getty ImagesBipartisan support is growing for a US sovereign wealth fund.The Alaska Permanent Fund, which distributes money to Alaska residents annually, could be a model.Challenges include funding sources, legislative hurdles, and state-owned natural resources.Bipartisan momentum is building around a sovereign wealth fund that could help the United States reduce its national debt or fund ambitious projects.At the White House, President Joe Biden's top aides have circulated plans for a fund to finance national security interests.