Most of us encounter handshakes at business meetings and when we're greeting someone, often for the first time.
But when is a handshake more than just a handshake?
At Nelson Mandela's memorial service on Tuesday, President Barack Obama shook hands with Cuban President Raul Castro. Some said the president should have snubbed Castro on the gesture.
But did Obama's gesture mean anything?
Politically, the handshake has had a checkered and controversial past.
Former Presidents Richard Nixon and Harry Truman shook hands with Mao Zedong and Joseph Stalin, respectively. The former wished not to insult the Communist Chinese leader, while the latter believed he, Stalin and Churchill were unified in rebuilding post-Nazi Europe.
Twenty years ago, Palestine Liberation Organization Chairman Yasser Arafat reached first in the direction of Israeli Prime Minister Yitzhak Rabin, who first sported what seemed like a puzzled look, before placing his hand firmly into Arafat's.
Palestine's Hamas, an Islamic resistance movement, exploded suicide bombs on Israeli buses soon after and Rabin died a mere two years later, at the hands of an Islamic extremist. Both Palestine and Israel are still "at war" with each other today.
Former President Bill Clinton shook hands with Communist dictator Fidel Castro of Cuba during a meeting of world leaders at the United Nations in 2000. It was such a politically-sensitive subject that the White House changed its story several times on the matter.
Obama shook the hand of Scott Brooks, head coach for the NBA's Oklahoma City Thunder, and then shook the hand of Thunder superstar Kevin Durant. Some were upset that Brooks, a white male, and Durant, an African-American, got a different handshake. (Handshake from :11-:16)
Some have even gone so far as to suggest nixing handshakes altogether, instead advocating a "fist bump" to help reduce the spread of germs. The president and first lady Michelle Obama bumped fists on the campaign trail in 2008.
Ultimately, handshakes can play an important role in negotiating or be merely gesture of respect. The handshake's intent -- political, polite or racial -- lies only in the mind of the handshaker.
Rob: Obama and Castro's handshake is just a handshake -- nothing more, nothing less. If the U.S. ends up going into talks with Cuba in the future, then maybe it was more than a handshake, but until then, there is nothing to imply otherwise. It is also time we update our stance on Cuba. I'm not going to overanalyze how Obama shakes a white coach's hand and Kevin Durant's hand.
Karie: I think it's just a handshake, as well. Handshakes can play a role in everyday business but not a large one. It's just like if you see someone at the Christmas party you don't necessarily like, but you aren't going to snub them of a handshake solely for that reason. You will shake hands, because you don't want to disrespect someone.
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