Thanks to a provocative Fox News format that compelled candidates to actually answer questions instead of reciting talking points, voters now know more about the 17 GOP presidential candidates. Overall, the dual debates offered these clarifications: The GOP has a deep field of plausible presidential prospects. And Donald Trump is not one of them.

Trump's thin-skinned, shallow answers to legitimate questions about his boorish behavior, business record and ideological inconsistencies revealed a candidacy mostly about himself instead of Americans. Sure, for some, he may have hit a nerve on immigration, as suggested by Ohio Gov. John Kasich. But Republicans should be unnerved watching Trump emerge as what he consistently criticizes: a dodging politician.

Fortunately for the GOP — and the country, since every American should want the best candidates nominated — several alternatives proved worthy of further consideration. Kasich himself showed the hometown crowd, as well as the record audience for a primary debate, that he's a substantive candidate. He has credentials as a deficit hawk and a governor concerned enough about the poor that he accepted Medicaid expansion even though Obamacare remains radioactive with Republicans.

Florida Sen. Marco Rubio also impressed. Like Kasich, he understands those at the economic margins because of his modest background. But a focus on foreign policy, not middle-class economics, is what set Rubio apart. Many will disagree with him on specific issues, but he fundamentally understands and articulates geopolitical complexities more than most others on stage.

That includes Wisconsin Gov. Scott Walker, whose rhetoric does not suggest requisite expertise on global affairs. At the debate he mostly focused on his successful electoral record and anti-union stance. But he unsatisfactorily answered a question on Wisconsin's middling economic performance, of particular note in Minnesota, where a more progressive political model has been accompanied by better economic results.

Jeb Bush did have a successful economic record while he was governor of Florida during its boom years. But for a former front-runner rich in campaign cash, he has yet to shine. True, his debate performance produced no gaffes, but neither did he seize the national narrative the way his father, brother or even Mitt Romney did as establishment favorites.

Others had their moments, including Texas Sen. Ted Cruz, who had a resolute, if not rallying, demeanor. But Ben Carson did not seem ready for the presidency, and Mike Huckabee was a good communicator but had a polarizing message. The most riveting, and important, exchange came when New Jersey Gov. Chris Christie and Kentucky Sen. Rand Paul sparred on the balance between security and privacy.

Subsequent debates need more of that kind of substance. And they should include Carly Fiorina, who dominated the earlier debate. Like Trump, Fiorina is an outsider with a business background. But unlike the front-runner she has the gravitas to earn her spot on stage.