US Secretary of State Antony Blinken heads today to Mexico in hopes of showing headway in tackling surging migration, which has climbed to the top of political headaches for President Joe Biden as he enters an election year.  

The unusual Christmas week trip by the top US diplomat was abruptly scheduled as the rival Republican Party presses Biden for a migration crackdown in return for agreeing in Congress to one of his key priorities – support for Ukraine.