It's been almost two years since Iran began to emerge from its international isolation after signing a deal with world powers to ensure its nuclear program is "peaceful." It's been almost as long since Justin Trudeau was elected prime minister on a platform that included restoring diplomatic ties with the country.

Last week, we learned Canadian officials are in Tehran for the first time since the previous Conservative government broke off relations with Iran nearly five years ago.

Since coming to power, the Liberals have been careful to remain critical of Iran's human rights violations, and have reiterated Canada's opposition to its support for listed terrorist organizations such as Hezbollah.

But Canada has also suggested engaging with Iran may change its behaviour, including on human rights and Iran's habit of jailing and abusing Canadian citizens and residents.

"We believe that open and frank dialogue, especially when we disagree, is the best way to effectively address security issues, hold Iran to account on human rights and advance consular cases," Alex Lawrence, a spokesperson for Foreign Affairs Minister Chrystia Freeland told CBC.

Western nations, including Canada, have been engaging or trying to engage with Iran since 2015.

So how are human rights in Iran and Canadian consular cases progressing?

Iran executed as many as 437 people between Jan. 1 and Oct. 25, 2016, according to a Human Rights Watch report, which cited other human rights groups. Many executions in Iran are not reported, making exact numbers difficult to trace. Dozens on death row are there for crimes allegedly committed when they were children.

Members of Iran's Baha'i religious minority, many with ties to Canada, are subjected to horrendous persecution. The group's leadership council is in jail.

Women are forced to wear headscarves, are harassed by police and are ratted out by undercover agents. Iran's morality police have also reportedly targeted barbershops that give men "Western" haircuts.

As for consular cases, former Canadian resident Saeed Malekpour has been jailed for almost a decade, accused, among other charges, of propagandizing against the Islamic Republic.

Concordia University professor and Canadian citizen Homa Hoodfar was released by Iran last September, after more than 100 days in Tehran's Evin Prison.

Concordia University's Homa Hoodfar spent more than 100 days in Tehran's Evin Prison. (Ryan Remiorz/Canadian Press)

Before Hoodfar was freed, Omar Alghabra, parliamentary secretary for consular affairs, said Canada's efforts to secure her release were complicated because Canada has no embassy in Tehran. While diplomatic relations worked in that case, they didn't save Canadian photojournalist Zahra Kazemi, who, in 2003, was jailed at Evin, tortured, raped and murdered.

On the international stage, Iran continues to prop up Syrian dictator and mass murderer Bashar al-Assad, who recently decided to have another go at using poison gas against children. His first large-scale efforts, after all, resulted in only a scolding and a sham deal to give up his chemical weapons stockpiles. He's likely been deterred now because of American cruise missiles sent by U.S. President Donald Trump, but Iran has hardly restrained him.

Iran is meanwhile preparing to hold presidential elections later this month. Of the six approved candidates, the incumbent, Hassan Rouhani, who negotiated the nuclear deal, is considered a moderate. Almost 1,000 Iranians were hanged under his watch in 2015.

All this to say, whatever the merits of engaging with Iran might be, improving the lot of Iranians doesn't appear to be one of them.

Almost 1,000 Iranians were hanged under Rouhani's watch in 2015 (Beawiharta/Reuters)

This doesn't necessarily mean Canada shouldn't have diplomatic relations with Iran. Canada has official ties with all sorts of obscene regimes — Saudi Arabia, which enjoys a multi-billion dollar arms-buying partnership with Canada, comes to mind.

But it would be refreshing if Canada were more candid about the tawdry nature of these relations. Trudeau once dismissed the weaponized armoured vehicles Canada sells to Saudi Arabia as "jeeps" — a ridiculous statement, but one that was easier to square with his government's supposedly more principled foreign policy.

Canada's relationship with Saudi Arabia results in money, jobs and, ironically, an alliance with the leader of a bloc of Sunni Arab states opposing Iran — whose ambitions in the region Canada generally opposes.

What Canada gets out of restoring diplomatic ties with Iran is harder to discern: more convenient travel for Iranian Canadians and their relatives, certainly, and the possibility of modest trade and business deals down the road.

That might be enough for Trudeau's government, and if it is, he should say so. But if Canada is to claim engaging with Iran will help Canada "hold Iran to account on human rights," it should explain why this is so. That would be a difficult argument to make. There is little evidence to support it.

This column is part of CBC's Opinion section. For more information about this section, please read this editor's blog and our FAQ.