In 1961, President Kennedy used it, when speaking about Canada: “Geography has made us neighbors.  History has made us friends. Economics has made us partners.  And necessity has made us allies.  Those whom nature hath so joined together, let no man put asunder.  What unites us is far greater than what divides us."

President Obama also used the idea in his 2009 speech on Martin Luther King Junior Day: “through times of great challenge and great change, we have remembered that fundamental American truth - that what unites us is always more powerful than what divides us.”

The Secretary-General of the United Nations, Ban Ki-moon, loves it.  First, in April of 2009: “What unites is so powerful it could easily overcome what divides us.”  Next, in London in November 2009: “We are united by the belief that what unites us as human beings is stronger than what divides us.”  

And now, Martin McGuinness - the Deputy First Minister of Northern Ireland - draws on the phrase at a conference last month.

It evokes powerful meaning. However, overuse will dilute such meaning. This phrase is at risk of becoming a cliche - at which point, as advised by Orwell, we should bin it altogether. 

So leaders, speakers, use it sparingly!