No topic is more important to President Donald Trump’s political agenda than immigration. And since July 1, 2015, he has used one case – the tragic death of Kathryn Steinle – as his sounding board to demonize immigrants, call for mass deportation, and demand an end to “sanctuary” policies which limit the role of local and state governments in enforcing immigration laws. And now, Trump is urging passage of legislation that would turn local police departments into a federal deportation force.