[Insert group here] Unite!

How do you rally a diverse group of people and unite them?

Every effort that can be made to stir up solidarity and pride will invariably leave someone out. There has never been a social movement that has included everyone that it tried to involve. The early American feminists stemmed from the abolitionist movement, but they did very little to address the concerns of black women. Even today, feminism is dismissed as a white, middle-class women's movement and many minority feminists have had to be larger-than-life speakers and activists like Audre Lord and Angela Davis to get any much-needed attention. Any nationalist movements in countries all over the world have left out people who didn't fit the definition of being a patriotic citizen. Labor unions, though claiming to be about workers' rights, have had histories over being selective about who they let in, who they left out, and how they treated their members. Hell, the first sexual harrassment lawsuit was filed against a union by one of its own members (watch the film North Country to learn all about it!). Americans were all in a tizzy about being "patriotic" after September 11th, but this led to a huge amount of backlash against liberals (by saying they weren't patriotic) and a surge of hate speech and crimes against Arab Americans and Muslims (by falsely linking them with terrorists, even though Muslims are one of the largest religious minorities in the country).

So how do you unite any group successfully? Or are there always some people who will be left out? And how do we decide who is left out and who may stay?
And who decides, anyways?