LAST weekend’s US presidential debate made uncomfortable watching, even with the sound turned down. Donald Trump prowled like a predator behind Hillary Clinton, deliberately invading her space in a provocative attempt to unsettle and bully her.

With the sound turned up, it was even more uncomfortable watching, Mr Trump making a slew of allegations which culminated with the ultimate intimidatory threat to have her locked up.

In the front row were three women whom Mr Trump claimed had been sexually abused by Bill Clinton and whom Mrs Clinton had “viciously attacked” in order to smear their stories.

It was extraordinary TV.

Even more extraordinary are the polls, which even now, even as the Republican hierarchy deserts Mr Trump, show Mrs Clinton pulling only slightly ahead. From my corner of the couch, I would have thought every American would have rushed out and voted for her – unless, of course, there is something in the dirt that Mr Trump so liberally throws.

And many American women do think there is a whiff to Mrs Clinton’s role in her husband’s affairs. In the early days, she defended him robustly – nothing wrong with loyalty, but the Clintons did try to dig up the pasts of the claimants as if it was the women’s fault for leading the most powerful man in the world astray.

Mr Trump accused Mrs Clinton of deleting 33,000 emails after being subpoenaed to release them by a congressional committee investigating an attack in Benghazi, in Libya, in 2012 in which four US diplomats were killed. Again here there is a whiff of truth.

During her four years as secretary of state in charge of security, Mrs Clinton conducted her affairs through a private email address, saying it was easier having all her emails in one inbox on one phone rather than getting a government address. This is probably true, but it meant that none of Mrs Clinton’s official emails were archived and none of them can be accessed by freedom of information requests.

At the end of her term, she had amassed 62,350 emails. Her team began weeding out the personal ones – about things like her daughter’s wedding preparations – so they could hand over the 30,000 official ones, and this deleting exercise coincided with the committee’s demand to see the Benghazi papertrail.

So, if you want to find a conspiracy theory, there’s one staring you in the face: Mrs Clinton tried to edit the papertrail.

Similarly, you could construct a theory around the Clinton Foundation, which Mr Trump describes as “the most corrupt enterprise in political history”. Charity regulators give it a clean bill of health for its wide-ranging work around the globe, but it raises much of its money through donations from global corporations and ridiculously wealthy individuals. Mr Trump says it is “pay to play” – you donate and the Clintons will ensure you get what you want somewhere in the world.

There’s little evidence of backhanders, but it is so far being transparent that even genuinely neutral observers feel the foundation should be suspended if Mrs Clinton becomes president.

So while the appalling Mr Trump has an approval rating of minus 63, Mrs Clinton is only a little better, on minus 53. She’s an automaton politician from the upper echelons of the establishment, hair and teeth designed by a focus group, at a time when voters the world over are tired of the self-serving elite and would prefer an untried, exciting outsider.

But, despite all the whiffs, for the sake of the planet, she has to win.