Since I was released from captivity in Iran in January 2016, Iran has continued its 40-year habit of taking foreign nationals hostage. I write about this issue extensively, in large part because it seems as though there is a new case every month.

But of the many innocent people being held as political leverage by the regime in Tehran, there is one case that has, from the very start, been harder than the rest for me to stomach.

Wednesday marks three years since Nazanin Zaghari-Ratcliffe, a wife and mother who is a British-Iranian dual citizen, was detained at an Iranian airport as she and her little girl were preparing to return to London after visiting her family for the Iranian New Year.

She was separated from her daughter, Gabriella — who was just under 2 years old at the time — and thrown into solitary confinement. Iran’s hostage-taking machine fired up its twin engines: a state-funded propaganda campaign and a fake legal process.

Her husband, Richard Ratcliffe, who was waiting for the return of his wife and daughter, has not seen either since.

“There is something deliberately outrageous in detaining a mother of a young child on a family holiday and holding her as leverage while smearing her as a spy,” he told me. “Back then, I didn’t realize such politics existed.”

Ratcliffe has become an eloquent and outspoken advocate for his family despite the daunting circumstances he has found himself in. Sadly, the obstacles he has faced have included the reluctance of the British government. The reunion of one’s innocent family should not require a massive public awareness campaign that has involved gathering more than 2 million signatures on a petition, a theatrical play and celebrity supporters.

But Iran’s hostage takers are stubborn and patient. They will wait to get what they want.

Three years in Evin prison is a long time — twice as long as I spent there — and the audacity of Iran’s state-sponsored hostage-taking is matched only by the absurdity of the supposed legal pretexts that its authorities conjure up.

“Even now it is shocking, for Nazanin and all the others from Europe and the U.S. held in Iran on trumped-up charges, that it has been allowed by our governments to go on for so long,” Ratcliffe said.

Zaghari-Ratcliffe stands accused of the vaguest sort of national security offenses by the intelligence wing of Iran’s Revolutionary Guard Corps (the same goons who took me hostage). I won’t go into the details of what they claim are her crimes against the Islamic republic. To do so lends a measure of credibility — however faint — to Iran’s insistence that this is a domestic judicial matter. Nothing could be further from the truth. It’s clear enough that the only reason Iran has targeted her is her citizenship.

We must focus on gaining Zaghari-Ratcliffe’s freedom as quickly as possible, but we must also accept that — as criminal as Iran’s hostage-taking is — we shouldn’t expect that regime to suddenly do the right thing and release Zaghari-Ratcliffe and other detained foreign nationals.

Only through the intervention of the home government — in this case, Britain’s — will these innocents return home.

Citizens of Western countries have long taken for granted that our governments would ensure our safety when traveling overseas. We assumed that our elected officials could generally be counted on to protect us from harm at the hands of foreign powers. That assumption of safety, though, seems to diminish with every fresh case, and Zaghari-Ratcliffe has suffered for it.

Something does finally seem to be changing, though. In Jeremy Hunt, Britain has a foreign secretary who understands the full insidiousness of the problem of state-sponsored hostage-taking. This is a tactic of pirates and terrorist organizations, and it can’t be allowed to become a normal tool of government policy. It must be rooted out. And the Iranian regime, which has often resorted to this most primitive tool of statecraft, must be punished in a way that will deter the practice in the future.

“I hope the international community — the U.S., the U.K., the U.N. — will finally make it clear this practice must end,” Ratcliffe told me. “Hostage-taking is not just devastating for our family and others like us. It also brings no good to Iran.”

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