Malachi O'Doherty: It is more complicated than simply humouring Irish-America, Mary Lou
What does Sinn Fein stand for? Obviously for a united Ireland, presumably to be achieved through a border poll.
And for the Good Friday Agreement, because they say so.
Yet the simple act of walking behind a banner which demands that England get out of Ireland throws all this into question.
According to the Good Friday Agreement, England can not simply "get out".
That would betray a core principle of the Agreement that the consent of the majority in Northern Ireland must determine whether we stay in the Union or go.
Indeed, the only party to the Union, ironically, that has no say in whether we are in or out is Great Britain.
And this is so at odds with the traditional republican reading of our historic subjection to imperial rule that it probably would be difficult to explain it to Irish-American chauvinists raised on the old simplifications.
So perhaps Mary Lou McDonald is due a little sympathy.
She gets invited to stand behind a banner with an 18th century slogan and she either has to keep smiling or take someone aside and give a lecture on how things have changed.
Easier to just go along with the old "wrap the green flag round me" tripe and endure a green beer at the end of it.
For don't we all know that Irish-America doesn't get it?
And there is probably a better chance of getting support dollars out of them while they are misreading the problem.
Of course, the other possibility is that Mary Lou doesn't actually understand the Good Friday Agreement either.
She stood before the party conference when she was appointed president and assured the faithful that this generation would see "the rising of the moon".
She likes the sentimental codswallop herself.
There's no need to unpack the meaning and remember that the "rising of the moon" stands for the resumption of the war when orders come from the captain and "the pikes will be together".
Surely Mary Lou was not actually threatening a return to armed struggle?
Of course not.
It's much more reasonable and plausible to assume that she just has an unfortunate knack of hitting the bum note.
Or that, at worst, she just gets an occasional heady lift from the recital of the rebel tradition.
Perhaps she feels that she has to ham up her affectation of republican ardour because she doesn't have the stripes.
It would be altogether more reassuring if Mary Lou could demonstrate that she understands the complexity of the problem she is trying to solve.
For that, she needn't wholly empathise with the DUP.
But she might at least acknowledge the steps taken by her own party.
Those steps were away from anticipating a future war and towards accepting that the problem is not simply that England has invaded and refuses to leave.
Britain has already acknowledged the right of Northern Ireland to secede from the UK on a majority vote.
I suspect many of them would be keen on us doing that as soon as possible.
As many again probably wouldn't even notice if we did.
Okay, she has to humour old Irish-Americans who think the answer is for England to go home.
And if they really are so behind with developments, one can pity the effort it would take to explain the 20th century to them.
So long as we don't have to explain it to Mary Lou.
And I'm not so sure we don't.