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President Obama: 'This was an act of terror and hate'
05:27 - Source: CNN

Editor’s Note: Julian Zelizer is a professor of history and public affairs at Princeton University and a New America fellow. He is the author of “Jimmy Carter” and “The Fierce Urgency of Now: Lyndon Johnson, Congress, and the Battle for the Great Society.” The opinions expressed in this commentary are his.

Story highlights

Julian Zelizer: Presidential candidates weigh responses to Orlando shooting to show they are best on national security

He says throughout history, how candidates have used crises has allowed voters to ponder how they'd lead under threat

Zelizer: Trump and Clinton social media reactions open them up to criticism from the other

CNN  — 

As law enforcement officials sort through the rubble at Pulse nightclub in Orlando, and learn more about how America’s deadliest mass shooting unfolded, the presidential candidates will be posturing to ensure that they use this moment wisely.

Hillary Clinton and Donald Trump don’t want this event to detrimentally affect their respective claims to be America’s best bet on national security.

But while the kind of politicking that results will feel unsavory to voters on both sides of the aisle, it can also offer a real opportunity for a serious conversation about the choices the nation faces and what it will mean, in this dangerous world, to have either of these candidates in the most powerful position in the country.

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Muslim leader to ISIS: 'You do not speak for us'
01:08 - Source: CNN

Indeed, whenever terrorism strikes in the middle of an election year, the parties need to adjust their campaigns in response to news. While Americans love to hold onto a nostalgic claim that politics stops at the water’s edge, nothing can be further from the truth.

Political campaigns are profoundly affected by unexpected national security crises, and whether they want to or not, candidates will need to offer politicized responses to make sure their opponent does not get the best of them.

For example, throughout the Cold War, conservative Republicans hammered away at Democrats for being weak against communism. Liberals responded that the right was dangerous and could not be trusted with the responsibility of nuclear weapons.

The battles over Vietnam were handled in a highly politicized fashion: liberals attacked President Lyndon B. Johnson, saying he was conducting an immoral and unnecessary war; Republicans attacked Johnson for not being tough enough; Johnson attacked everyone for undermining his authority in the middle of this crisis.

While there was a fleeting moment of bipartisanship following the attacks of 9/11, Republicans have hammered away at Democrats ever since for underestimating the threats we faced.

The horrendous massacre in Orlando, Florida, is no different. With 50 people dead and 53 injured, the nation is aghast and frightened.

Both of the party candidates offered their responses. Through Twitter, Donald Trump, in characteristic fashion, unleashed a series of short-form comments: “Horrific incident in FL. Praying for all the victims & their families. When will this stop? When will we get tough, smart & vigilant?”

The next one read: “Appreciate the congrats for being right on radical terrorism, I don’t want congrats, I want toughness & vigilance. We must be smart!” Soon after he let out another, “Is President Obama going to finally mention the words radical Islamic terrorism? If he doesn’t he should immediately resign in disgrace!” And so on.

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Witness: 'No bullet could ever break a friendship'
02:44 - Source: CNN

His formal press release was not any calmer. Trump warned that, “Obama disgracefully refused to even say the words ‘Radical Islam’. For that reason alone, he should step down.” He also warned that “Hillary Clinton wants to dramatically increase admissions from the Middle East, bringing in many hundreds of thousands during a first term – and we will have no way to screen them, pay for them, or prevent the second generation from radicalizing.”

Hillary Clinton responded on Facebook in a more restrained fashion. “This was an act of terror. Law enforcement and intelligence agencies are hard at work, and we will learn more in the hours and days ahead. For now we can say for certain that we need to redouble our efforts to defend our country from threats at home and abroad. That means defeating international terror groups, working with allies and partners to go after them whenever they are, countering their attempts to recruit people here and everywhere and hardening our defenses at home. It also means refusing to be intimidated and staying true to our values.”

The terrorist act will offer challenges to the campaigns as they try to figure out the best response to the situation.

Trump will continue to boast that he was right, and that the events at this nightclub somehow confirm his warnings about radical Islamic threats here in the United States.

But the turmoil and fear the attacks raises will spur more questions and concerns from some voters about whether Trump can be trusted with the awesome responsibility of handling a terror attack; whether he has the knowledge, the temperament, the wisdom and the demeanor to guide the nation through these kinds of events.

Indeed, his tweets might themselves become fodder for critics who want to argue that his knee-jerk response is proof positive that that he can’t be trusted with military power and responsibility.

The attacks, which are a new episode in the long history of violence against homosexual Americans, will also be a powerful reminder about the dangers of some of the angrier attacks that Trump has unleashed on different social groups here in America.

Trump has consistently attempted to downplay what he calls “politically correct” attacks on the kinds of words he used, but the particular nature of this attack offers Americans a look at what kinds of actions can be produced by different kinds of social hatred.

Though we don’t know the motivations or psyche of this particular attacker, the fact that it was conducted at Pulse suggests that anti-homosexuality was a driving force. In June 2015, the world celebrated “Love Wins.” Today the world mourns.

Clinton, too, will find herself under attack as a result of Orlando. As Trump’s tweets suggest, he and other Republicans will use this tragedy to raise questions about the experience and long record that is a pillar of her campaign. Trump will point to the attacks as proof that the administration has not been aggressive enough in the fight against ISIS and that it has refused to map out a strategy for dealing with lone-wolf attacks on soft targets.

For Trump, the horrific attacks, as his tweets suggest, will be a way to justify controversial statements that he has made about Muslims and immigrants.

It is easy to wish that politics and national security won’t mix at times like these. But they will. As long as they do, we must take the time to think through carefully how this nightmare would be handled with either of our candidates in the job of commander in chief.

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