The Lead With Jake Tapper

DOW plunges 1,000+ points on coronavirus fears; Gains in 2020 now wiped out; Italy has largest cluster of coronavirus outside Asia with 215+ cases, seven deaths; New SC poll: race narrowing, but Biden still leading; Candidates ramp up attacks on Sanders ahead of critical 9 days; Moderate Dem attacks Sanders' partial defense of Castro; Bloomberg advisor: other candidates "don't deserve to win" if they can't find courage to challenge Sanders at debate; GOP's Scott: Sanders is biggest threat to Donald Trump; Biden denies calling SC his firewall, despite saying exactly that; Sources: Trump want fewer people working for him, more loyalists; Trump adviser: Ginni Thomas leading effort to compile list of "never Trumpers"; Sources: Trump's new personnel chief warns agencies to look out for disloyal staffers; 100% of NV vote in; Sanders solidly in 1st, Biden 2nd; Source: national security advisor O'Brien's instincts may be "political", O'Brian contra