How is Trump winning the US immigration debate?

About

"With border crossings reaching record highs in recent years, immigration has returned as the US election’s most toxic issue. "As Donald Trump continues to push a policy of mass deportation, and Kamala Harris responds by shifting further to the right, what happens to the people caught in the middle trying to seek a better life? The Guardian’s Oliver Laughland and Tom Silverstone head to Arizona’s southern border with Mexico to investigate" (Guardian)