Like many Americans, we plan to take Memorial Day off. And while a three-day weekend is always fun, this holiday is a somber one.

We were reminded of that reading an Op-Ed from Tom Manion in today's Wall Street Journal . Manion served in the military for 30 years and his son, Travis Manion, was killed in Iraq when he was just 26-years-old.

Manion delivers an emotional piece that attempts to answer a complex question: Why do they serve?

His son had an easy answer, telling him that "If not me, then who?"

But the sacrifices are enormous and many times tragic. Yet even after a decade of war, Americans still volunteer to serve. That, writes Manion, is the "essence of our country."

We encourage you to click over and read the full piece .

We'll leave you with a stunning photograph taken in Boston today, where 33,000 American flags were planted to represent the Massachusetts soldiers killed since the civil war:

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