We're talking about all things politics on In Depth:  a Supreme Court vacancy, global and regional impacts of a trade war, and much more.  KCBS Political Analyst Marc Sandalow is a guest on In Depth from Washington DC, beginning with President Trump's pick to replace the retiring Justice Anthony Kennedy on the High Court.  Pres. Trump has announced he will make an announcement via Twitter, and we consider how much is at stake for him -- perhaps not so much for him, necessarily -- but for America?  As Sandalow points out, the pick will be dissected by people.  But, it may be the single most impactful decision of his presidency -- considering how long the pick may stay on the High Court.  It will be the difference between the majority being a conservative majority or a much more mixed court.  This is an extraordinarily consequential decision, Sandalow argues.  And, the President understands that, he believes.  Also on the docket for discussion on In Depth:  the beginning hours of trading after what appears to be the start of a trade war with China, and how the Bay Area views the ongoing debate over border control and immigration policies.  Constitutional Law professor Rory Little weighs in with remarkable insight about how decisions in Washington impact residents in the Bay Area -- and beyond.