America is sliding into a winter limbo of alarming spikes in Covid-19 cases and deepening economic pain while an apathetic lame duck White House and a deadlocked Congress provide no political leadership.The darkest holiday season in modern history beckons, yet President Donald Trump and his closest aides, sulking after his election defeat, are doing little to save lives, apart from claiming credit for a vaccine that represents a way out of the nightmare of 2020 but remains months away for most Americans.