LONDON — If the 2016 American presidential election has polarized opinion at home, it appears to have united much of Europe in collective dismay: How could Donald Trump have come so far, many wonder, and the level of discourse sunk so low?
Europeans always seem to be scolding Americans for what they say is a low standard of debate. But European politics is no stranger to childish name-calling, xenophobia, lurid sex scandals and financial corruption.
For all the foibles of their own political system, however, many British people see the American presidential race as having crossed an obvious but invisible line.
Mixing the personal with the political — such as dredging up a candidate's personal history for political ammunition — is far less tolerated in Europe.
"As political parties, you don't exploit these scandals," said Iwan Morgan, professor of U.S. Studies at University College London. "There's always a convention that you let the [news]papers do it."
That's why Trump's personal attacks, and even Hillary Clinton's repeated references to her becoming America's first female president, strike many here as problematic.
NBC News went to the House of Commons and asked Londoners what they thought of the election.
"I think we always knew the second debate would be much more personal," said Peter Couchman, who runs a community fundraising organization. "I think it's disappointing that it's virtually only personal."
Another passerby, Maureen Cole-Burns, who is the chief operating officer at the National Institute of Economic and Social Research, added that the candidates had been "dragging [politics] into the gutter."
She added that, "as a British person watching that, it lowers America in my estimation."
That's not to say that British or European politics are somehow tame. Parliament's raucous "Prime Minister's Questions" weekly session is "like feeding time at the zoo," according to Morgan at University College London. He added that British newspapers are also relentless in their pursuit of lawmakers' personal faults.
But for British politicians, the barriers of good taste are very clear.
A member of parliament was forced to resign from a prominent committee leadership after recordings of him discussing drugs with male prostitutes surfaced this summer.
But when another lawmaker called David Cameron "Dodgy Dave" and made allegations about the then-prime minister's personal finances, he was kicked out of the parliamentary chamber and chided by the speaker of the house.
The story in the newspaper was deemed fair game, the allegation by the fellow politician was not.
Furthermore, Home Secretary Amber Rudd was widely derided as a bigot earlier this month when she vowed to "flush out" companies who employed foreigners over Brits — a proposal that might seem quaint by Trump's standards.
This can be explained in part by the difference in political cultures across the pond. British voters are more likely to stick with the party they have always chosen, perhaps diminishing the influence of a firebrand speaker, an inspiring personal history or a sordid scandal on any given race.
As a consequence, European politics can seem like a more staid, serious affair.
"The political confrontation in the United States may seem exotic to Europeans," said a staff editorial in France's top paper, Le Monde, following Sunday's night's debate.
The paper pointed to the theatrical quality of America's interminably long campaigns. But the second debate, it said, was nevertheless a "reflection of how Trump has degraded the democratic game."
Questions of political culture aside, Europeans tend to prefer Clinton to Trump because their political preferences lie further left.
President Barack Obama's election, and his eight years in office, impressed many people abroad who had lost hope in the American political system during the deeply unpopular years of George W. Bush.
"I've lived in America before for a number of years and I was pretty impressed when they elected Obama. I saw that as a step forward," said Maureen Cole-Burns outside the House of Commons.
Trump's rise to within striking distance of the White House, she said, was like "two steps back."
Even after nearly eight years in office, Europeans hold a mostly favorable image of America's 44th president. Some 77 percent of Europeans have confidence in Obama to do the right thing in world affairs, according to a Pew Research study this past summer.
The same study found that 59 percent of Europeans had confidence in Clinton compared to only 9 percent who had similar esteem for Trump.
In short, if Europeans voted, the U.S. presidential race wouldn't even be a contest.
"For someone who's who's looking to represent America, which is obviously the superpower of world, it's the wrong person," said Londoner Keith Heaven, speaking outside the House of Commons. "I'm sure a lot of people in England think that way."