Jen Psaki, a CNN political commentator and spring fellow at the Georgetown Institute of Politics and Public Service, served as the White House communications director and State Department spokeswoman during the Obama administration. She has worked as a consultant for Planned Parenthood Federation of America. Follow her: @jrpsaki . The opinions expressed in this commentary are hers.

(CNN) As a mom, the scenes from the terrorist attack in Manchester make me want to lock my daughter up in her room, ban her from attending concerts and shut out the world. And she is not even two years old. Fear is a human response. But it is also what the terrorists are after.

The images and stories of the young victims that begin to emerge in the coming days will put our resolve to not be afraid to the test. And it is times like this when we need the President of the United States to be a steady voice -- one who acknowledges the human reaction to tragedy, but who also guides us away from allowing fear to morph into prejudice and hatred.

But this kind of leadership will require a new approach from the Commander in Chief, one that differs from what he has said and done in the past.

In the days after the Paris attack, for instance, then-candidate Donald Trump called for banning all Muslims from entering the United States and for building a registry that would ensure we knew the identity of all of the Muslim-Americans living peacefully among us.

He stoked anger against Muslims and helped spur, across the country and among members of Congress, a fear of refugees that led in part to more stringent restrictions on refugee resettlement.

I was working for President Barack Obama at the time, and our own reaction from the White House to the Paris attack was not perfect either. We were so wrapped up in our own outrage at Donald Trump's attacks on the Muslim community, and against refugees, that we failed to focus enough of our energy on communicating to the public the strengths of our own system -- our law enforcement, our vetting process, and our own protections to keep the American people safe.

President Obama was also criticized at the time for not reacting to the attacks with more emotion, with more anger . Some of that criticism was justified. He was on a trip in Asia, and was not digesting the raw reaction in the United States.

His answers during press conferences were wrapped in the steady and pragmatic tone that had long been his signature. But in the days following the attack, he also didn't do enough to acknowledge the impact of the attacks back home.

While his approach was frustrating to many of us in the White House in the moment, his steady calm proved in retrospect to contain wisdom as well. He refused to get into a race to the lowest common denominator, to heighten his own language or ways of thinking to mirror the fear and emotions of the people in the country he led. He told us that he needed to be the voice of reason. He was right.

It has been 18 months since the Paris attack. There is a new President in office.

He may not want to take a page out of the calm and steady Obama playbook, but I hope he can at least learn from how the people of Manchester, citizens who have lost neighbors and classmates and children, have already responded. Muslim taxi drivers are offering free rides in the city. Citizens are banding together

We are in some ways more vulnerable to reactive prejudice in the United States. The population of Muslim Americans here pales in comparison to countries like the UK, where Muslims are about 15% of the population in Manchester, according to the last census in 2011.

Yet there is not a flood of talk about kicking Muslims out of the city. There is not a movement by even the conservative leadership of the United Kingdom to register Muslims or ban entry of Muslims into the country.

There is an effort at the grassroots level to live together. To stand together.

The true challenge of events like Manchester is not how we respond with sympathy for the victims, and anger at the " evil losers " (as our President has called them) in the immediate aftermath, but in how we react in the days to come.

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If history is a guide to how President Trump will react in the weeks ahead, we have reason for concern.

As citizens, we must hope he will not use this horrific attack as an opening to turn anger and fear into discrimination and either way, resolve not to let that happen.