I want every American to understand why it did happen, says Obama
National monuments were barricaded on Tuesday, US war cemeteries in Europe closed, and hundreds of thousands of federal workers were sent home without pay, after dawn revealed the wreckage of America's latest paralyzing political crisis.
Thousands of federal workers trekked into town only to clear their desks and be told they were not "essential" to running the US government machine.
Young aides trooped out of the White House, leaving Obama with only a skeleton crew on hand.
The military and border patrol were kept at full strength, but the Pentagon was due to stand down almost half of its 800,000 civilian employees.
Warring lawmakers, exhausted by Monday night's political theatrics, stirred under the serene Capitol Rotunda, but early hopes that a compromise would emerge once the shock of the shutdown had hit proved premature.
President Barack Obama accused conservatives in the House of Representatives of waging an "ideological crusade" by making government funding conditional on gutting his landmark health care law.
His top foe, Republican House Speaker John Boehner, meanwhile claimed Obama was pursuing a "scorched earth" policy by refusing to negotiate, as the rhetoric hit new heights and hopes for a swift end to the standoff faded.
The president was in feisty form at a White House event marking the rollout of a key portion of Obamacare, which turned into an extended taunt at Republicans for failing to halt implementation of the sweeping law.
"This Republican shutdown did not have to happen -- I want every American to understand why it did happen," Obama said.
"They have shut down the government over an ideological crusade to deny affordable health care to millions of Americans."