Mohamedou Ould Slahi is the author of “Guantánamo Diary.”

During the 14 years I spent cut off from the world in the U.S. prison in Guantanamo Bay, I often found myself wondering whether people cared about the conditions under which I was being held. Since my release a little more than one year ago, I’ve been impressed by how many people do care — something that has been driven home to me again by the public reaction to reports of a change in policy toward artwork created by inmates in the prison. For several years, the U.S. government had a screening process that permitted artwork created by prisoners to be shared with family members and others outside the prison, but in November it announced it is no longer allowing prisoner art to be publicly released. As a result, these works can no longer be seen by anyone outside of Guantanamo. What’s more, the government has been saying that it owns the works of art and can destroy them if it wishes. I have been heartened by the individuals and organizations that have protested this cruel policy, as well as by the critical coverage in the U.S. and international press.

But I can’t say that I was surprised by the news itself.

In October 2014, one of my guards came to my cell to warn me that I would soon be moved to another block. I asked what I could take with me to the new cell. He said I could take only my copy of the holy Koran, nothing else.

And so, in the blink of an eye, I was separated from the life that I had built around me in that cell over the previous 10 years. That life, for me, included writing. It included a journal in which I recorded my life and thoughts in the years since I completed the manuscript for my “Guantánamo Diary,” which I wrote and delivered in a series of letters to my attorney in 2005. It also included stories I had written about my childhood, fictional stories and even a manuscript for a book I was working on called “Portable Happiness,” about how to stay positive in the most hopeless situations.

I never saw these things again. They disappeared, along with movies, books and other items that were given to me as gifts, sent to me by my family members or brought to me by my lawyers to provide me comfort. That is what they call these things in Guantanamo: “comfort items.” The comfort of these things, for me, was that they really were mine: They were things I had created and things that my lawyers, family and even interrogators and guards had given to me personally. They were expressions of myself and expressions of what others saw in me. They were proof that I existed.

What I learned that day was that those “comfort items” were given to me and to other detainees only so that our jailers could have another kind of leverage over us: to build a cloud of anxiety that anything we created or were given could at any time be taken away. They said, essentially, that today you may have something, but tomorrow you will again have nothing, because you are nothing.

Today, the U.S. government is still holding these parts of me. It did not return my manuscripts and scribblings after my shackles were finally removed when the military plane landed in my home city of Nouakchott, Mauritania, and it has not returned them to this day. It can do this, it claims, because these things I wrote are “classified.” It can do this because — in the words of a Pentagon spokesman who was interviewed about the new policy preventing the paintings and sculptures of Guantanamo prisoners from ever being seen outside the prison — detainee art is the “property of the U.S. government.”

I was born in a part of the world where freedom of speech and expression are a rare commodity, and I know dictatorial methods when I see them. I left my home country in North Africa just after high school to move to Germany so that I could live a life where I could say what was on my mind without being afraid that I would be kidnapped, killed or put in prison. I am not alone in this. Ask any person who emigrated from the Middle East to Europe or the United States to escape suppression of freedom of speech and expression, and they will tell you: I am what I believe, and if I cannot express it clearly and unequivocally, I am no one.

The censorship and human rights violations that are taking place in Guantanamo Bay have long been practiced in my part of the world. They do not work. They do nothing but demean us — all of us. As a positive person, I have to hope that the current policy of confiscating and permanently suppressing the artistic creations of Guantanamo detainees will be reversed. I hope this for the 41 prisoners who are still in Guantanamo, many of them unjustly. But not just for them. The United States deserves better than this, too.