The broad executive action on immigration that President Obama announced on Thursday night could shield nearly half of the population of an estimated 11 million undocumented immigrants now believed to be in the U.S. from deportation. But the move is much bigger than that. The president is also directing the government to fundamentally reshape its priorities for enforcing immigration laws by focusing more intensely on removing criminals rather than families, overhauling immigration courts, and making changes to the high-skilled visa system.