If White House loses patience with us, so will US investors
Last month Martin McGuinness let slip that the US regarded St Patrick's Day as the deadline for progress on the Haass proposals on flags, parading and the past.
Since then, people have rowed back a bit on that, and it won't be the end of history if the impasse continues a little longer.
Yet there is no doubt that any parties seen by Washington as holding back progress will lose both brownie points and goodwill.
Northern Ireland enjoys extraordinary access in Washington but that could be scaled back if engaging with our leaders appears to be a waste of time. Without positive messages of support from the White House about the stability of our peace process it will be harder for us to attract US investment.
Investors will certainly draw their own conclusions if Barack Obama is seen with Enda Kenny but avoids Peter Robinson and Martin McGuinness.
That is the sort of soft power the US wields and on this issue, Washington is united across the political spectrum.
Mr Obama is a liberal Democrat, Mr Biden prides himself on his Irish Catholic roots, and Dr Haass is a fairly hawkish Republican on many issues. He was one of George W Bush's special advisers and heads a centre-right think tank.
Yet it would be hard to put a leaf of shamrock between the positions of these three men on Northern Ireland.
If they appear together at some point on St Patrick's Day, that will be a signal to Northern Ireland over how strong the feeling is for compromise and how little sympathy there is for the digging in of heels.
That is why St Patrick's Day is so important this year. It can boost our image or hurt it.