YouGov finds 49% think the Trump visit should go ahead
Petitions are a rubbish way of measuring public opinion. In fairness, that isn't actually their purpose - a petition is a way for individuals to record and express their opinion, a way of highlighting an issue and exerting pressure. They can indeed be very good at that job. Some people however assume that because a vast number of people sign a petition it must, therefore, reflect wider public opinion. That is not the case - if a million people sign a petition hey are not necessarily representative of anyone but themselves. It shows only what those themselves think, the rest of the population may think the opposite, but not be bothered to sign petitions about it (and some demographic or attitudinal groups may just be more inclined to express their opinions through petitions).
So it appears to be with the petition on the Trump visit. Well over a million and a half people have signed a petition against the visit, but a YouGov poll in the Times this morning shows 49% of people think the visit should go ahead, only 36% think it should cancelled (Though it's important to note the poll question does not relate to the petition specifically. The poll asked if the visit should go ahead at all, the petition is about the more technical issue of whether it should be downgraded from a full State Visit).
This does not mean there's a silent majority of the British public who like Donald Trump - quite the opposite, British public opinion is very hostile about him and getting worse. 62% now think he will be a poor or terrible president (up from 54% just after the presidential election) and people here are overwhelming negative about his policies. The ban on refugees and visitors from seven Muslim countries gets the thumbs down from 50% of British respondents and the support of only 29%. Other policies are even less popular (67% think his wall is a a bad idea, similar figures disapprove of his environmental policies)
One can only assume that the public think the invite to Trump should stand despite their dislike of the man and his policies because, like it or not, he is the leader of a country we need to work with. Asked what the attitude of the British government should be towards trump 51% say we should try to work with him, rather than distance ourselves from him (32%). Opinion there is moving swiftly though - there has been a large drop since November when 66% thought the government should work with him.
I do ponder what sort of reception Donald Trump will get of the visit goes ahead. The British public really don't like him, and if that petition doesn't measure the balance of opinion, it probably does give us a good idea of the pool of people available to turn up to any visit to protest. That said, there have been plenty of State Visits by unpopular world leaders in the past that have been managed without incident. I just wouldn't count on too many large public events...