WASHINGTON — When congressional committees meet this week to begin formally drafting Democrats’ ambitious social policy plan, they will be undertaking the most significant expansion of the nation’s safety net since the war on poverty in the 1960s, devising legislation that would touch virtually every American’s life, from conception to aged infirmity.Passage of the bill, which could spend as much as $3.5 trillion over the next decade, is anything but certain. President Biden, who has staked much of his domestic legacy on the measure’s enactment, will need the vote of every single Democrat in the Senate, and virtually …
