Here are the key moments from the debate that brought Republican presidential candidates head-to-head in North Charleston, S.C. on Jan. 14. (Sarah Parnass/The Washington Post)

President Obama suggested Tuesday that the United States may not, in fact, be on the verge of total collapse. The Republican presidential candidates responded in Thursday’s GOP debate by painting an even more dismal and dangerous picture than they had in the past. The president is a traitor. The military is a shell of a fighting force. The economy is a shambles. Average families are in grave danger. If Democrats win, the country is lost.

With only a few weeks left before the first primary contests, the GOP race has devolved into a competition for who can squeeze the most political advantage out of voter fear, no matter how over-the-top they sound and no matter how much damage they do by darkening the national mood. Sen. Ted Cruz (Tex.) “won” the latest round of this increasingly disgusting show, with Donald Trump and Sen. Marco Rubio (Fla.) coming in second. But being the most effective at exaggerating the dangers the country faces and preying on voter anger is not an achievement; it is a moral failure.

Here is the world according to GOP:

“Barack Obama does not believe that America is a great global power,” Rubio said. “Barack Obama believes that America is an arrogant global power that needs to be cut down to size.” This was a reprise of Rubio’s line last week that “Barack Obama has deliberately weakened America.”

Obama “acts as an apologist for radical Islamic terrorism,” Cruz said.

“The world has been torn asunder,” former Florida governor Jeb Bush insisted. “In this administration, every weapon system has been gutted,” he said. (Really? Every one?) Also, he said, “Hillary Clinton would be a national security disaster.”

New Jersey Gov. Chris Christie hit that theme hard: “If you’re worried about the world being on fire, you’re worried about how we’re going to use our military, you’re worried about strengthening our military and you’re worried most of all about keeping your homes and your families safe and secure, you cannot give Hillary Clinton a third term of Barack Obama’s leadership.”

Former neurosurgeon Ben Carson said the president has “done everything he can to diminish” the military, and he speculated about the Islamic State hitting the United States with electromagnetic pulses, dirty bombs and cyber attacks so devastating that the country would cease to exist.

Donald Trump added: “Our military is a disaster. Our healthcare is a horror show…. We have no borders. Our vets are being treated horribly. Illegal immigration is beyond belief. Our country is being run by incompetent people.” Migrants, he also said, “could be the great Trojan Horse. It could be people that are going to do great, great destruction.”

“China is running over President Obama like he is a child,” Cruz added.

“The damage [Obama] has done to America is extraordinary,” Rubio said. “Let me tell you, if we don’t get this election right, there may be no turning back for America.”

If “a progressive gets in there and they get two or three Supreme Court picks, this nation is over as we know it,” Carson warned.

Here is a dose of reality: It is possible to disagree with the GOP base and be a patriot. The nation faces many challenges, but it is stronger economically and more secure from various foreign threats than nearly everywhere else in the world. In many ways, Americans are better off now than they ever have been. The continuing desire of non-Americans to move, work and do business here is a sign of strength, showing the appeal of the United States rather than demonstrating weakness.

For those of us with who don’t see national destruction looming around every corner, there were a couple of somewhat encouraging moments Thursday night. One of them: Bush insisted that Trump is “unhinged” for insisting that no Muslim should be allowed into the United States, arguing that the country needs to build relationships with peaceful Muslims.

But that moment of moral competence was only impressive by comparison with practically everything else the candidates — including Bush himself — said Thursday night.