American soldiers might stop patrolling the streets and head back to their barracks. Help to the Iraqi army could suddenly cease – not to mention raids on Al-Qaeda fighters and Shiite extremists. US and Iraqi officials would scramble for options to salvage their mission here, in the waning, lame-duck days of a Bush administration that launched and pursued the war. It's a vision of what may take place if Iraq's parliament refuses to accept a new security agreement with the US before year's end. That date – Dec. 31 – is when a UN mandate expires and with it, the legal basis for American troops to operate inside Iraq. No one knows for sure what will happen if that D-Day comes and passes with no done deal. But the options are growing more stark amid the growing chance – almost inconceivable before – that US forces could indeed find themselves with no legal authority to operate in Iraq, come the morning of Jan. 1, 2009. Would Iraq's army and police, in the blink of an eye, be left on their own to maintain security in a country still reeling from the savagery of the last five years? Would security gains won by the sacrifice of more than 4,100 Americans and tens of thousands of Iraqis be at risk, in that same sudden moment? Without American support, “security may deteriorate ...Al-Qaeda and the armed groups might resume their activities and the militias might return to the streets,” Foreign Minister Hoshyar Zebari told Alhurra television Thursday. Iraq may yet decide to approve the deal, especially if the US agrees to changes. Nearly every major decision made in Iraq comes only after protracted haggling and complex bargaining – all done in an atmosphere of deep suspicion among the various religious and ethnic parties. That means it's still too early, with November and December ahead, to say this brinksmanship process has reached a lasting stalemate. One influential Iraqi official, the Shiite deputy parliament speaker Khalid Al-Attiyah, said Thursday that he hopes for a decision soon – either for or against the deal. The pact would remove American forces from Iraqi cities by June 2009, with all US troops out of the country by the end of 2011, unless both sides agree to an extension. But the security agreement faces real problems – clearly more serious today than anyone imagined just a few weeks ago. Iraqi leaders are torn between desire for continued US help and the yearning of many Iraqis for an end to what they consider foreign military occupation. Prime Minister Nouri Al-Maliki has refused to submit the draft to parliament unless he is certain of strong backing. He fears rivals will use the agreement against him in provincial and national elections next year – a real possibility in a country exhausted by nearly six years of war and eager to end outside domination. For their part, most of his Shiite rivals also want the deal privately, but are demanding big changes. They clearly see the negotiations as a way to give Al-Maliki political problems. Others like anti-US cleric Muqtada Al-Sadr are against the deal. Sunnis – who may want the deal most of all – don't want to stick their necks out first, to push for its passage in the current form. They fear being branded traitors, a charge that still sticks on Sunni tribes that supported the British in a revolt nearly 90 years ago. Meanwhile, the United States has indicated the last thing it wants is to reopen any points already negotiated with Al-Maliki. America's top commander, Adm. Michael Mullen, warned this week that time is running out and that Iraqi officials may not fully appreciate the situation's seriousness. So far, the United States has been mum on how it might manage what is certain to be a chaotic, fast-moving series of events at year's end if the deal isn't done – after a new US president has been elected but almost a month before he takes office. If the agreement appears doomed, Pentagon spokesman Geoff Morrell says the US plans to ask the UN Security Council to extend the mandate authorizing military operations in Iraq. But that could get complicated if Russia and China, with vetoes in the UN Security Council, press for changes in the mandate before approving it. They might want new restrictions on US operations, or a shortened time for the US to remain in Iraq. Those are touchy issues that a lame-duck Bush administration might find hard to negotiate. The Russians say they will support an extension if Iraq asks for one, but Iraq is reluctant to do that. Asking for an extension would open Al-Maliki to charges he's attempting an end-run around the government's own democratic institutions to maintain a US military presence. Yet without a new UN mandate or a broader bilateral deal, there are few options. The United States and Iraq could try to negotiate some limited deal, but Al-Maliki's foes might try to block even that. One top Al-Maliki aide says that if the larger deal falters, “we will sit down and look for an alternative.” He spoke on condition of anonymity because the situation is so delicate, and he also gave no timetable. All that leads rather alarmingly to Jan. 1, 2009. American commanders have not spelled out in detail what they would do – in terms of day-to-day operations – in the absence of an agreement on that date. Without a legal framework, however, US soldiers would be in violation of international law if they continued military operations. At a minimum, that would probably require commanders to keep soldiers on bases, while diplomats and legal experts figured out what to do. In the end if things really went awry, it could be yet another unresolved and complicated crisis, left for a new American president to solve.