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Obama spoke Tuesday in Milan with several buttons undone
Since leaving the White House, he's displayed a more casual style
It feels like every time we see former President Barack Obama, he loses another button.
On Tuesday, he was speaking at the Global Food Innovation Summit in Milan, Italy, where he defended the Paris climate accord, but viewers noticed something else … his deeply unbuttoned shirt.
Since leaving office, Obama has dressed more casually in public than he usually did as president.
Here he is back in January on his last day in office, wearing a tie.

Two weeks ago, here he is at his first public event since leaving office, looking cool and casual in a suit jacket and open-collared shirt, sans tie.

And again last week, showing off the proposed Obama Presidential Center.

Then here he was Tuesday unbuttoned in a striped shirt …