A platform for dissent: As they tour the world, David Cameron and Barack Obama have a duty to speak out against corruption and repression

David Cameron is in no doubt why he is flying to Malaysia and Indonesia this week. He will be “packing a plane full of business people”, he wrote in a national newspaper last week, and going to South-east Asia to sell, sell, sell. “My message to South-east Asia is simple,” he went on. “When it comes to new markets, Britain means business.”

And what if the people we mean to do business with are crooks? There is the little matter that William Hague used to talk about when he was Foreign Secretary: ethical foreign policy. It got a mention near the bottom of Mr Cameron’s article, but only a brief and baffling one. “[People say] we should avoid doing business with countries with barriers to trade, including corruption,” he said. “Wrong again. Many in South-east Asia have led the battle against corruption ... Britain is joining them in that fight – I’ve put the issue at the top of the global agenda.”

If corruption is that important, can we expect Mr Cameron to ask his Malaysian counterpart, Najib Razak, about the apparently well-sourced allegation that nearly $700m (£451m) has been paid into Mr Najib’s personal bank accounts from companies connected to a controversial investment fund, 1MDB, which he helped to launch? It is important that he does.

The Malaysian Prime Minister is livid about the allegations, but The Wall Street Journal, where they first surfaced earlier this month, is sure enough of its ground to have repeated them. The charges have astonished a Malaysian public, wearily familiar with scandals of every sort. Mr Najib’s so far fruitless efforts to silence his accusers have included blocking a whistle-blowing website, Sarawak Report, which reported the story, and having his Home Affairs Minister threaten to extradite its British editor to Malaysia, to stand trial for “interfering in the country’s sovereignty”. This came after the leader of the opposition, Anwar Ibrahim, was imprisoned for “sodomy” last year.

However strenuously Mr Cameron insists that his driving concern is Britain’s bottom line, he cannot ignore the fact that his visit will confer an aura of international respectability on a regime that, in more than one regard, has serious questions to answer.

Mr Obama’s visit to Ethiopia today, the first by a US president, risks having the same unfortunate consequences. Ethiopia’s strong economic recovery over the past decade has yet to see it tackle chronic mass poverty, while soaring unemployment, the rising cost of living and political repression induce thousands to make desperate attempts to reach Europe. Human Rights Watch says its “repressive laws ... constrain civil society ... and target individuals with politically motivated prosecutions”.

The Ethiopian People’s Revolutionary Democratic Front, which has been in power since 1991, contrived to win all of the seats in the recent elections, including the single constituency formerly held by the opposition. As 14 Africa experts wrote in an open letter to the US President: “Your visit may send the message that the US is giving [its approval] to the profoundly repressive policies pursued by the government.”

Western leaders need to realise the extent to which their visits can cast a rosy glow on rulers who do not deserve it, in the process betraying the hopes of millions who look to Western democracies, with all their faults, as beacons of liberty. We are not suggesting that these countries should be shunned, especially when, as with Ethiopia, they are bulwarks against terrorism. But in the fever to “grab every opportunity”, the need to make unwelcome observations must not be overlooked.