01:31 - Source: CNN
GOP debate in 90 Seconds

Story highlights

Without insults, antics, Trump's policy weaknesses on display, says Tara Setmayer

She says he repeatedly boasted of negotiating and deal-making skills, but flubbed important questions

Editor’s Note: Tara Setmayer is former communications director for Rep. Dana Rohrabacher, R-California, and a CNN political commentator. Follow her on Twitter @tarasetmayer. The opinions expressed in this commentary are solely those of the author.

CNN —  

Imagine if every GOP debate had been like the one Thursday night. Policy heavy, insult light and providing voters with a contrast between the candidates over level of knowledge on issues. It was clear that each candidate had shifted tactics from the last dumpster fire of a debate.

After Sen. Marco Rubio’s mudslinging with Donald Trump hurt his campaign, he decided to return to his above-the-fray, aspirational tone. Sen. Ted Cruz avoided the schoolyard back and forth with Trump as well, but still managed to hit him on specific policy differences. Gov. John Kasich was…well, Kasich.

READ: 5 takeaways from the Republican debate

For his part, Trump showed no signs of the thin-skinned, petulant reality show star we’ve become accustomed to throughout this campaign. No bluster. No insults. But also no energy. And no real policy knowledge.

How different would the campaign be at this point if this Donald Trump had shown up from the beginning? Imagine if the tabloid antics and outlandish behavior never happened. Imagine if Trump’s positions and record were actually vetted? Would this Trump have been as popular or capable of building his cult of personality without the shtick? I think not.

02:32 - Source: CNN
Donald Trump pressed for specifics of his worldview

READ: Trump - ‘Islam has tremendous hate’

If this election had been about policy, not personality, from the beginning, Donald Trump wouldn’t have made it past the first primary. At Thursday’s debate, both Rubio and Cruz effectively exposed Trump’s unworkable position on trade and his lack of substance on major foreign policy issues.

This wasn’t the first time Trump was made to look foolish on important foreign policy questions. Who can forget his utter incoherence when asked about the nuclear triad a few debates back.

What made this debate different was Trump’s inability to hide behind his usual obnoxious bullying tactics to distract from his ignorance. He appeared to be trying to tone things down, I assume to prove to detractors that he does have the temperament to be President. But he left himself exposed as the policy neophyte that he actually is. Pithy catchphrases does not a foreign policy make.

01:30 - Source: CNN
Marco Rubio: 'The climate is always changing'

READ: Trump or Cruz - Republican leaders shake their heads

Trump looked uncomfortable. When challenged on substance, he consistently pivoted back to his talking points about making “great deals.” While Rubio and Cruz spelled out policy positions – on, for example, Cuba and Israel – Trump showed that he was out of his league on topics that a President should be well versed in.

He utterly flubbed his explanation for praising Russian President Vladimir Putin and calling the brutal communist Chinese government’s massacre at Tiananmen Square “strong,” by arguing the meaning of the word. It recalled the infamous Bill Clintonesque answer of “it depends on what the meaning of the word ‘is’ is.”

Over the last few weeks, Trump’s opponents have been hitting him hard on his “flexibility” on key stances he’s built his campaign on. From his hardline on immigration to tough talk on torture, Trump often speaks out of both sides of his mouth. Yet, the most telling moment of the night came when Trump was asked what else he would be flexible on and he replied, “you never know.” Is that so?

01:26 - Source: CNN
Does it matter how the world sees the U.S.?

Here is the crux of what so many have cautioned Trump supporters about. Trump is a political chameleon capable of changing his positions based on what he thinks best suits him politically at any moment. Trump’s answer Thursday night showed his candidacy to be purely cosmetic, not one of honest conviction. This should be worrisome to the supporters who think they are getting one thing when they may really be getting something else.

Isn’t that exactly what has fueled the groundswell of anger at the politicians in Washington? A major part of Trump’s appeal is that he portrays himself as an outsider. But is he really? As Carly Fiorina so aptly pointed out, how can Trump reform “the system” when he’s admittedly been a part of it?

02:35 - Source: CNN
Donald Trump, Marco Rubio spar over Cuba

READ: Why Americans are so angry

Although Cruz and Rubio had solid performances, it may be too little too late to change Trump’s trajectory.

Trump is a master at manipulating people to buy what he’s selling. But this time it’s not his steaks or mortgages or real estate classes. It’s the presidency of the United States, and once they’ve realized they’ve been had, the American people cannot join a class action lawsuit to ask for their money back.

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Editor’s note: Tara Setmayer is former communications director for Rep. Dana Rohrabacher, R-California, and a CNN political commentator. Follow her on Twitter @tarasetmayer. The opinions expressed in this commentary are solely those of the author.