warsaw president barack obama pledge saturday seek ways calm racial tensions reduce divisions police minorities final months office warn easy access gun nationwide exacerbate problem obama speak end week five policemen kill sniper dallas two black men kill police minnesota louisiana say would bring together civil right law enforcement leaders talk white house next week return trip europe obama first black u.s. president speak racial issue throughout time white house also try fail reform american gun laws stymie republicans congress oppose measure see impinge constitutional right bear arm despite series mass shoot recent years obama say dallas police force reduce murder rat community complaints take issue race police conduct seriously say hop would inspire constructive action come weeks spirit need embrace spirit want build say press conference poland divisive issue gun control could separate tension police local citizens say obama note dallas police thursday protect citizens sniper fire decipher gun among take part protest decry police shoot black men presence gun car philando castile 32 kill police minnesota wednesday contribute event say minneapolis know yet happen know gun car apparently license cause fashion tragic events obama tell reporters ignore pretend somehow political ... contribute factor sole factor contribute factor broad tensions arise police communities serve obama unlikely succeed revive major gun control reform leave office january lawmakers congress fight three rival gun measure since june 12 mass shoot gay nightclub orlando democrats promise put pressure republicans next week win vote measure expand background check allow justice department block gun sales people government watch list obama say saturday hop legacy issue race would one urge americans listen understand country difficult relationship race legacy slavery jim crow discrimination suddenly vanish passage civil right act vote right act election barack obama say say hop word president convey things get good substantially good still get lot work do u.s. gun rule heighten tension police citizens obama