I want Morning Star readers to get out their pens and start writing "Dear Chelsea," because Chelsea Manning is a political prisoner and writing letters to political prisoners has three recognised effects.

First, such letters can make prisoners of conscience feel stronger.

Given the sacrifices Manning has made exposing war crimes, we owe her that.

Second, letters make prison authorities treat political prisoners better. Even in authoritarian regimes, prison guards are sensitive to world opinion.

They don't want to be left carrying the can for any bad behaviour when political conditions shift, especially as the lower ranks know they are most likely to be thrown out in the rain when the political weather changes.

Manning suffered inhumane conditions in her first imprisonment at the Quantico US military base, including solitary confinement and removal of clothes.

International protests helped get her a more normal prison regime, so we have already seen protest bring changes for this political prisoner.

Third, a big postbag will show the US government that we won't forget our best people and so keep up pressure for change.

Manning was sentenced to 35 years for espionage, but she is no spy. She revealed widespread evidence of war crimes in Iraq and Afghanistan.

The "war logs" she passed to WikiLeaks showed US and allied forces killed thousands more civilians than they admitted.

They showed that US and allied troops were shooting men, women and children at checkpoints.

They showed that allied forces were allowing their Iraqi allies to torture captives.

They showed that unregulated mercenaries were killing Afghan and Iraqi people with no legal authority and no comeback.

Manning did the right thing by revealing war crimes. But she is in prison while the killers go free.

Her imprisonment is a political decision to try to shut up critics of murder under orders.

The "secrets" Manning revealed by leaking diplomatic cables are also political "secrets."

Far from causing harm, the diplomatic cables actually helped to launch the Arab spring.

The cables are more complex than the war logs - it would take a dozen columns to describe what important truths lie in them, so I won't try.

But every day throws up some new, important news. Last year a WikiLeaks diplomatic cable showed that in 2005 US and Australian diplomats were secretly scheming to kick Mohamed el-Baradei out of his job as leader of the International Atomic Energy Authority (IAEA), a position that put him in charge of UN atomic weapons inspectors.

The US hated Baradei because he showed that "intelligence" touted by Washington on Iraq's WMD were ridiculous forgeries.

The US was also angry because he would not rubber-stamp its claims about Iranian nuclear programmes.

Thanks to Manning we know Australian officials were secretly trying to undermine UN weapons inspectors without telling the Australian people.

Manning joined the US army under her former name Bradley Manning. Her lawyer announced she wanted to change gender just after she was sentenced, although she has been wrestling with identity issues for some years throughout her time in the army.

Much of the press have been pretty respectful of her wishes, which is a sign of the vast change in attitudes to sexuality that have taken place in my lifetime thanks to the hard work of thousands of LGBT activists.

Prison authorities will not recognise her chosen name, so you need to write to:

Bradley E Manning
89289
1300 N Warehouse Rd
Fort Leavenworth KS 66027-2304
USA

But you can use the salutation "Dear Chelsea."

Manning is not Fort Leavenworth's only "celebrity" prisoner.

Other inmates at what is properly called the "United States Disciplinary Barracks" have included Charles Graner, one of the prison guards who tortured people in Abu Ghraib.

He's not there any more. Graner was sentenced to 10 years' jail - less than a third of Manning's sentence - but only served six of them.

Lieutenant William Calley, who was found guilty of the murder of 104 civilians in the Vietnam war's My Lai massacre, had an even shorter stay.

He was transferred to house arrest in 1971 after serving just one day of his sentence in Fort Leavenworth.

Three years later Lt Calley was pardoned by Richard Nixon.

These were men who committed real, brutal crimes - and also irreparably damaged the US's international status.

But Manning would be a lot happier if she got their sentences.

I hope letters from Morning Star readers can make her jail time a little shorter.