It has become a mantra among senior American officials that the United Nations risks irrelevance if it does not deliver a resolution that authorises, or can be read to authorise, the use of military force to disarm Iraq.
"Failure to act [against Saddam Hussein] would embolden other tyrants, allow terrorists access to new weapons and new resources, and make blackmail a permanent feature of world events," President George W Bush has said.
Is it more damaging for the UN to authorise war or not to?
"The United Nations would betray the purpose of its founding, and prove irrelevant to the problems of our time."
Speaking to the Security Council in January US Secretary of State Colin Powell said: "This body places itself in danger of irrelevance if it allows Iraq to continue to defy its will without responding effectively and immediately."
The Security Council appears to be in a terrible bind.
If it refuses to back American plans in Iraq, it will be sidestepped as Washington leads a "coalition of the willing" to war.
Once bypassed, the argument goes, the UN is severely compromised as an organisation which can build consensus and provide legitimacy for international action - military or otherwise.
If however the council does deliver a second resolution, it risks becoming irrelevant in the eyes of many Africans, Asians, Arabs, Latin Americans and Europeans who oppose war in Iraq and will see the council as a tool of American policy.
Non-Americans have been insisting that the UN and the council are meant to reflect the views of all 191 members, not just the US.
UN legitimacy questioned
Richard Perle, a senior advisor to the US president, recently asked: "Is the United Nations better able to confer legitimacy than, say, a coalition of liberal democracies?"
The question has been on conservative American lips for years. For most members of the current administration, the great effort required to mobilise the UN behind a particular action is simply not worth it.
Frank Gaffney, an assistant secretary of defence under Ronald Reagan, argues that the decision-making process at the UN Security Council should not be endowed with great importance or moral legitimacy.
Can coalitions of liberal democracies... do something about these security problems in the absence of any effective UN action, in the absence of a willingness to go beyond endless debate and hand wringing and irrelevant, feckless resolutions?
Former US assistant defence secretary
"We should understand that this process is being driven by national considerations. That's what's going on here," Mr Gaffney told the BBC's Broadcasting House programme.
"This is not some kind of higher moral entity where everyone leaves their national interests at the door and thereby arrive at some collective and more reasoned view, than say the United States acting simply under its constitutional processes."
In a post-Cold War era, Mr Gaffney argues, in a world of weapons of mass destruction and rogue states, we must look beyond a Security Council on which permanent members may have an interest in protecting these rogue states.
If consent is a guiding principle for our democracies at home, what is wrong with seeking consent at the international level?
Sir John Weston
Former UK ambassador at UN
"At this point, we must return to the question of can coalitions of liberal democracies that are seized of the need to do something about these security problems do so in the absence of any effective UN action, in the absence of a willingness to go beyond endless debate and hand wringing and irrelevant, feckless resolutions.
"I think the answer to that must be yes, because it really is the only hope for a world of greater security, rather than greatly reduced security."
Defending the UN charter
Sir John Weston, the UK's ambassador at the UN from 1995 to 1998, argues that the UN charter and the organisation's universal membership give its endorsement of the use of force a unique legitimacy.
"The United Nations, with 191 member states, is the place where we seek consent for action in the international field," Sir John told the BBC.
"I think the answer to the question of why people want to go to the UN is a simple one - it's the same reason that President Bush decided to go to the UN. That is that the charter... is the origin of the moral legitimacy of the world organisation.
It remains to be seen whether the UN will recover from this, but it has condemned itself
"A lot of people in our countries and elsewhere feel happier about the notion of proceeding to use of military force in a situation which is not one of direct self-defence when they can see that that decision is endorsed under chapter seven of the charter."
Chapter seven of the charter specifically provides for the use of force in such a situation when other measures have failed - provided the use of force is endorsed by the Security Council.
Wheeling a dealing
The apparent diplomatic haggling at the Security Council over who will vote for a second Iraq resolution has been widely criticised and seen to detract from the legitimacy of the decision-making process.
"I don't think that we should be too prissy about the notion that there could be an element of wheeling and dealing in the Security Council," Sir John Weston said.
"There is an element of wheeling and dealing in national politics and law making everywhere."
As we go forward into the rest of this century, and look at the really big problems of peace, social progress and the future of the planet, I think the rest of the world will regard it as disastrous if there were not a world organisation like the United Nations
Sir John argues that the UN is about gaining consent or maximising the degree of consent.
"If consent is a guiding principle for our democracies at home, what is wrong with seeking consent at the international level?
"As we go forward into the rest of this century, and look at the really big problems of peace, social progress and the future of the planet, I think the rest of the world will regard it as disastrous if there were not a world organisation like the United Nations where these things could be brought together and hammered out by consensus.
"That after all is the essence of the democratic process that we are so busy preaching to the rest of the world."
Can UN survive?
The US president has signalled unmistakably that he is willing to act unilaterally if the UN does not play the role that Washington insists it indicated it would by adopting Resolution 1441 last November.
"It remains to be seen whether the UN will recover from this, but it has condemned itself, and most especially the French and others who are vetoing or blocking action by the Security Council have made that very problematic," Frank Gaffney argues.
It is widely believed that a US-led war against Iraq without UN backing would damage the world body - and cement the independence and absolute nature of American power.
The UN's other roles - humanitarian and emergency relief, peacekeeping and nation building - might rescue the organisation, even in American eyes.
While diplomats battle over a new resolution at the Security Council, it is reported that other parts of the UN are already drawing up plans for a role in post-war Iraq.