Black Americans say racism and police conduct are the most important issues in their choice of candidates for president, are sharply critical of President Donald Trump on both matters and see increasingly high stakes in the outcome of November's election, a Washington Post-Ipsos poll finds. Former vice president Joe Biden currently leads Trump by a not-unexpectedly lopsided margin among black registered voters, 92% to 5%. His supporters are about evenly split on whether they are casting an affirmative or negative vote, with roughly half saying they mainly support Biden and the other half saying they mainly oppose Trump. Despite the overwhelming support he enjoys, Biden faces clear challenges in mobilizing younger black adults. This is a group that strongly disapproves of Trump but is also notably less enthusiastic about voting at all and is generally more critical of Biden than are older black adults. While 87% of black seniors say Biden is sympathetic to the problems of black people in America, that drops to 66% among those under age 40. Black Americans are evenly divided on the question of whether Biden, who has pledged to pick a woman as his running mate, should take an extra step and select a black woman. The poll finds that 50% say it is very or fairly important to them that he do so, while 49% say it is not. The choice of a black female running mate matters more to black women under age 40 than to those 40 and older. Joe Biden is cool but it would be great to have someone who can counter his perspectives on a lot of things, said Willa Ivory, a 31-year-old social worker who lives in New York City and who mentioned former Georgia gubernatorial candidate Stacey Abrams as a possibility. In order for Biden to get the black vote, he needs to pick somebody black because I think a lot of people are going to sit...