When Callista Gingrich, the nominee of President Donald Trump as U.S. ambassador to the Vatican, testified on Tuesday before the Senate Foreign Relations Committee, she insisted that the president is committed to sustaining the country's clean air and clean water. At the same time, a lot of netizens aired their opposition on social media to her nomination.

Even if Trump withdrew the U.S. from the Paris climate agreement, Gingrich, the wife of former House Speaker and Trump supporter Newt Gingrich, insisted Washington is not backing out of its commitments.

It is not the posturing of the U.S. being an environmental leader, however, that Callista's nomination is being questioned by some Americans.

Former mistress

Rather, it is her past as the mistress of Newt for six years while he was married that is being cited by some Twitter users who oppose her nomination. The Washington Post's headline captures a lot of sentiments of those opposed to sending her to the Holy See because her "nomination to the Vatican stinks to high heavens."

According to the newspaper, Callista was 23 years younger than Newt when they had a six-year extramarital affair in the 1990s when she was a House staffer and he was the House speaker. Newt also led the impeachment of then-President Bill Clinton who had an affair with intern Monica Lewinsky.

Her nomination is proof that the Trump administration has no lowest point, Blackbird Writes! tweeted. A Twitter user, who uses the handle "@Paul_O-Tix," urged Pope Francis, whom he described as seemingly a down-to-earth person, to keep the Catholic Church respectable and refuse to accept Callista, whom he described as a lying philanderer as the ambassador.

Party which celebrates family values

The irony of Callista's nomination, despite her being president of Gingrich Productions and Gingrich Foundation, was not lost on Michael Sean Winters who wrote in the National Catholic Reporter that a party which "celebrates family values at every turn" is led by a president on his third wife and who had boasted of his extramarital affairs.

In addition, he nominated as ambassador to the seat of the Catholic Church a woman "who had a six-year affair with her future husband while he was still married to his second wife."

Other publications, such as the Catholic News Agency, pointed out that Callista was instrumental in Newt's conversion to Catholicism in 2009. It also cited their production of two documentaries: "Nine Days That Changed the World" and "Divine Mercy: The Canonization of John Paul II" as proofs of her qualification for the position.

A blog post on Life Site, however, said Callista's extramarital affair will always be a chokehold on public perception and will likely remain in place because of the lack of show of repentance by the couple for their affair. Although the blogger believes the couple has repented, the issue would remain a large elephant in the room that many Americans would prefer to remain in the U.S. rather than send to the Vatican.