Silence over abuses of human rights and democracy such as those experienced in Uganda and Zimbabwe amounts to consent.

On Wednesday evening, Robert Kyagulanyi Ssentamu, known by his performing name Bobi Wine, was on stage with me for the launch of my new book, Rich State, Poor State, in Johannesburg.

Rich State, Poor State describes why some countries reform, and keep reforming, while others fail. One critical determinant is the nature of the system that allows competitive conditions to take root, permitting a battle for political ideas and governance as much as in business.

Wine said at the event that he would be returning to Uganda and believed that a mass welcome was being organised. He wondered aloud if he would be arrested once more. Then we sang the song Alone Together, which includes the line "Don't be a victim, be a solution".

On Thursday morning, on his arrival at the airport in Kampala, Uganda, he was detained by armed policemen and transported to his house where he was placed under house arrest, the type of harassment he has suffered continually since announcing his intention to enter politics to challenge Uganda's octogenarian President Yoweri Museveni, who has been in power since 1986.

My heart sank as I read his text message: "I was grabbed off the tarmac by the...