.Biden prepping to obstruct Nippon Steel investment of united state Steel The Washington PostU.S. Steel says it could possibly leave behind Pittsburgh if Nippon bargain flops as Biden considers to block out takeover Pittsburgh Post-GazetteBiden Expected to Block United State Steel Requisition The New York TimesExclusive|United State Steel Portend Plant Closings if Sale Collapses The Exchange JournalBiden prepped to block out US Steel investment by Nippon Steel CNN.