The process of closing down large parts of the US government was under way on Tuesday morning, after frantic rounds of late-night political sparring failed to avert the first federal shutdown in nearly two decades.  More than two million federal workers were told to go to work as usual, where they would be informed whether they were part of the "essential" core that would still work. An estimated 800,000 were due to be ordered home, although they could spend the morning setting out-of-office email alerts and preparing for an absence without pay that could last days if not weeks.  Some federal workers were reportedly instructed to switch off their BlackBerry smartphones to prevent them from working remotely, a disciplinary offence.  From 7am, forlorn-looking commuters could be seen heading to government buildings and agencies across Washington DC, where they would learn their fate. The city, where the government is a huge employer, will feel the impact of the federal shutdown more acutely than anywhere else in the US. The White House said it estimates a one-week shutdown would cost the wider US economy $10bn.  In a symbolic image of a country immobilised by political stalemate, the national parks service in the capital began the process of placing barricades around the Lincoln Memorial; museums were closed and water fountains that stretch along the National Mall were due to be switched off. In New York, the Statue of Liberty was closed to visitors.  Nasa's mission control center in Houston continued operations to support astronauts currently in space, but the rest of the agency's staff, such as those working for other government science and research programs, were told they would not be working.  People on social security will still receive their benefits and people on Medicare will still be able to see their doctor, at least in the short-term. Air traffic controllers, prison guards and border patrol agents will remain in post, but if the shutdown drags on long enough, their paychecks could be delayed.  The first shutdown since 1996, when Bill Clinton was president and Newt Gingrich was the House speaker, occurred after Republicans staged a series of last-ditch efforts to use a once-routine budget procedure to force Democrats to abandon or delay the healthcare reforms that were the signature of Obama's first term.  Three separate attacks on the Affordable Care Act, also known as Obamacare, were staged by the House, only to be rejected in turn by the Democrat-controlled Senate, which accused Republicans of holding the country to ransom.  Shortly before midnight on Monday, Senate majority leader Harry Reid marked the end of the process by rejecting House calls for formal talks to reconcile their conflicting positions.  "This is a very serious time in the history of our country," Reid said. "Millions of people are going to be affected tomorrow and the Republicans are still playing games."  Reid was due to reconvene the Senate at 9.30am on Tuesday to consider a Republican proposal to convene a bipartisan committee to resolve the impasse. However he had already declared his reluctance to give ground, telling Senate colleagues: "We will not go to conference with a gun to our head."  Referring to the conservative wing of the Republicans in the House, Reid added: "It is embarrassing that these people are elected to represent the country are representing the Tea Party."  The White House has drawn up a list of essential staff who are legally allowed to carry on working, but President Barack Obama warned that a shutdown would have an immediate effect on the fragile US economy.  "We do not have a clear indication that Congress will act in time for the president to sign a continuing resolution before the end of the day tomorrow, October 1," said a White House statement issued shortly before midnight.  "Therefore, agencies should now execute plans for an orderly shutdown due to the absence of appropriations. We urge Congress to act quickly to pass a continuing resolution to provide a short-term bridge that ensures sufficient time to pass a budget for the remainder of the fiscal year, and to restore the operation of critical public services and programs that will be impacted by a lapse in appropriations."  Obama also issued a statement to military employees after signing a Republican-proposed law that exempts active-duty servicemen from the effects of the shutdown, but will not protect civilian workers.  "I know the days ahead could mean more uncertainty, including possible furloughs," Obama said. "You and your families deserve better than the dysfunction we're seeing in Congress."  House speaker John Boehner denied that Republican tactics were responsible for the shutdown, insisting Democrats were to blame for refusing to negotiate over Obamacare.  "I didn't come here to shut down the government," Boehner told one of several heated House debates.  "I came here to fight for a smaller, less costly and more accountable federal government. But here we find ourselves in this moment dealing with a law that's causing unknown consequences and unknown damage to the American people and to our economy. And that issue is Obamacare."  But Democrats are confident that US public opinion will continue to hold Republicans to blame for what could be days of disruption until a deal can be struck.  They argue that Republicans are using underhand methods to overturn a law that was passed four years ago, ratified by the supreme court and endorsed by voters at the last presidential election.  Senator Bernie Sanders, of Vermont, said: "If we surrender to hostage-taking tonight, these guys would be back within a couple of weeks without a shadow of a doubt. What we are dealing with tonight is an extraordinary anti-democratic act."
Senate to reconvene after political sparring ends in stalemate and US enters first federal government shutdown since 1996