He also talked about the level of vitriol in political debate. He said a lack of civility in politics didn’t motivate the alleged shooter, Jared Loughner. In fact, he departed from the prepared text and firmly said, “It did not.” Obama used the opportunity, though, to appeal for unity among Americans and inspire hope about our political system. He asked all of us to live up to the expectations of our children and make our country as good as Christina Green – the youngest victim in Saturday’s shooting – imagined it.

They believed and I believe we can be better. Those who died here, those who saved lives here – they help me believe. We may not be able to stop all evil in the world, but I know that how we treat one another, that’s entirely up to us. And I believe that for all our imperfections, we are full of decency and goodness, and that the forces that divide us are not as strong as those that unite us.

That’s what I believe, in part because that’s what a child like Christina Taylor Green believed. Imagine for a moment: here was a young girl who was just becoming aware of our democracy; just beginning to understand the obligations of citizenship; just starting to glimpse the fact that someday she too might play a part in shaping her nation’s future. She had been elected to her student council; she saw public service as something exciting and hopeful. She was off to meet her congresswoman, someone she was sure was good and important and might be a role model. She saw all this through the eyes of a child, undimmed by the cynicism or vitriol that we adults all too often just take for granted.

I want to live up to her expectations. I want our democracy to be as good as Christina imagined it. I want America to be as good as she imagined it. All of us – we should do everything we can do to make sure this country lives up to our children’s expectations.

Watch the entire speech here:

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I’m not talking about a debate about gun laws, though that’s important, too. I’m talking about exploring why guns are so important to so many Americans. It’s not enough to say, “Guns are a part of our culture.” Why are they and violence a part of our culture? In a country where there is a gun for nearly every person, why are some people resistant to reasonable restrictions for firearm purchases? Why do some people feel the need to carry guns on them all the time, like Texas Gov. Rick Perry who carries a handgun while jogging? What motivates these men in Northern Virginia, a relatively high income, low crime area, to think that a criminal with a gun is around every corner, and therefore feel they must openly carry guns on their hips?

Watch the full episode. See more Need To Know.

I always got the feeling that machismo influences some of the more vocal and passionate guns rights supporters. Guns are powerful. They can extinguish lives. What better way to show strength than to hold that lethal power in one’s hands or strap it to one’s waist? The need to show that strength and power indicates a fear of something. Maybe it’s an insecurity about oneself. Maybe it’s fear of the government or fear of the guy down the block. Michael Moore explored the link between guns and the “fearful heart and soul of the United States” in his film Bowling For Columbine. Until we examine and confront that fear of the unknown, often fueled by imagination, guns will continue to be plentiful and there will be more shootings like the one in Tucson.

Lastly, a sad bit of irony: One of the first pieces of business for the new Congress this week was to vote on the repeal of healthcare reform. That, along with other House business, has been postponed because of the Tucson shooting. Many of the same congressmen who want to roll back healthcare reform support laws that allow the easy purchase of firearms. We have to re-evaluate our priorities. As a country, we need to figure out why so many feel that providing healthcare for every citizen is an American nightmare, but the reality of firearms for nearly every citizen is an American ideal.