What would a better US immigration system look like? We asked the experts.

WASHINGTON — Immigration, one of the defining issues of the Donald Trump era, posed an immediate challenge to President Joe Biden on taking office.

His administration struggled to address a sizeable upswing in the number of migrants arriving at the US-Mexico border.

And processing delays have led to what some lawmakers, but notably not the White House, have called a growing "humanitarian crisis," heightening political tensions in Washington.

Yet the situation at the southern border hasn't brought about action on Capitol Hill, reflecting the decades-long gridlock on immigration among lawmakers who often have sharply divergent views on the nature of U.S. immigration.