WASHINGTON – Once in a great while, a circumstance occurs that poses a clear-cut challenge to our nation and people to demonstrate that we truly are who we say we are.

Such is the current public debate over accepting refugees fleeing the civil war in Syria, specifically in the wake of the Islamic State terrorist attacks on the people of Paris.

Standing in New York Harbor to remind us is that long-ago gift from the French people of the Statue of Liberty, whose pedestal quotes the 1883 sonnet of poet Emma Lazarus. She called the lady with the torch “the Mother of Exiles” from whose “beacon hand glows world-wide welcome,” who cried “with silent lips, Give me your tired, your poor, your huddled masses yearning to breathe free, the wretched refuse of your teeming shore. Send these, the homeless, tempest-tossed to me. I lift my lamp beside the golden door.”

Perhaps no other American landmark better defines the high and generous purpose of this country to the rest of the world. President Obama put it in less poetic words at the 20-nation summit in Turkey.

Talking of the pushback from two dozen U.S. governors threatening to bar their own state doors to such refugees, most of whom are Muslims, he called a religious test “shameful” and “not American,” because “that’s not who we are.”

All but one of those governors were Republicans, and they were joined by several 2016 Republican presidential candidates favoring such a test for gaining entry into the United States, thereby bringing the issue smack into the ongoing campaign.

Beyond injecting a major new element into an already stormy debate over American immigration reform, the furor over admitting more Syrian refugees has obliged the Democratic candidates – Hillary Clinton, Sen. Bernie Sanders and former Maryland Gov. Martin O’Malley – to defend Obama, who already had called for admitting 10,000 more from Syria in addition to the some 2,000 already here.

More significant, however, is the new pressure on a Republican Party enduring the large field of presidential aspirants whose antics have already brought ridicule to their partisan brand.

Specifically, the 2016 election will determine the identity of the next American commander-in-chief of the armed forces and his or her own foreign policy, amid a dearth of experience among the GOP candidates.

The one Republican seeking the presidential nomination who can claim the most military experience, as a retired Air Force officer and member of the Senate Armed Services Committee, is Sen. Lindsey Graham of South Carolina.

His failure to garner even 2 percent support in the amalgam of polls determining participation in the latest Republican debate left him off the main stage.

He may well suffer the same fate in the next one, sponsored by CNN, in Nevada on Dec. 15.

Of particular interest in that coming debate will be how the two current Republican front-runners, Donald Trump and Ben Carson, respond to CNN moderators’ questions on countering the Islamic State and on the refugee issue.

Neither of them has demonstrated deep familiarity with those or other key foreign-policy matters. Indeed, a supposed Carson briefer dealing with the Islamic State has reported that the retired neurosurgeon did not seem to grasp much of the coaching given him. Carson’s response was that the man was not an adviser to him, and he balked at identifying who was playing that role on foreign policy.

All this demonstrates how the rogue military force of Islamic radical jihadists has succeeded not only in establishing itself as an agent of barbarism and fear in the West, but also has intruded in a major way on the American presidential campaign.

The three Democrats, Clinton, Sanders and O’Malley, all are essentially in support of Obama’s measured response to the terrorist threat.

The Republican field, though, seems united only in a generalized position of demanding that the president to be tougher toward both the enemy and the Syrian refugees.

In the weeks ahead, look for the GOP contenders to outdo each other in rhetoric, if not in concrete proposals.

Editor’s note: Jules Witcover’s latest book is, “The American Vice Presidency: From Irrelevance to Power,” published by Smithsonian Books. You can respond to this column at juleswitcover@comcast.net.)