Prime Minister Stephen Harper has described Iran in recent interviews as the gravest threat to international security, expressing certainty that the regime is striving to build nuclear weapons. Security experts may be more likely to contend that Iran is developing the potential to create nuclear weapons. The difference between these positions, however, may not be as meaningful as one would expect.

History has demonstrated that countries with nuclear weapons tend not to get attacked, enjoying greater latitude in their domestic repression and international belligerency. By the same logic, nuclear weapons capability could form a protective shield around the Iranian regime's brutal acts and further embolden its assassination attempts of foreign government officials; support of terrorist groups; meddling in other countries to foment violence and civil unrest; propping up of repressive regimes like Assad's Syria; translating into action its vitriolic hatred of and threats against Israel; and state-sanctioned arrests, beatings, detentions, kidnappings, torture, and ever-increasing executions of its own citizens.

The recognition of this threat has rightly convinced Canada and other Western countries to impose strong sanctions on Iran, but more can be done while still falling well short of military action.

First, Canadian sanctions can be tightened to intensify pressure on the Iranian economy and weaken the regime. The rial recently hit an all-time low against the dollar, and rampant inflation and high unemployment render the government vulnerable. Improved sanctions could unleash a domestic Iranian backlash that revives the internal opposition. Thus, we should eliminate the loophole that allows, for instance, a Chinese energy company to operate in Iran while its Canadian subsidiary operates in Alberta. Canadian sanctions should put companies to a choice between doing business in Iran and doing business in Canada.

Second, we need to do more to stop the bloodshed in Syria. This is important not only because thousands of civilians have been killed in the last year at the hands of a murderous regime. It is important also as part of our response to confronting the Iranian threat. Syria is Iran's greatest regional ally and strategic asset, and the collapse of the al-Assad dynasty would be a blow to Iran's reach.

Conversely, the weakening of Iran could help bring down the Syrian regime. Tehran continues to help Syria evade oil sanctions, enabling revenues from illegal oil sales to fill the government's coffers -- funds that allow Assad to continue his lethal repression of protestors. Canada and the West need to strengthen the Syrian opposition. This could mean providing the rebels with more sophisticated equipment, or utilizing international tools like the Responsibility to Protect doctrine.

Third, Iran's Islamic Revolutionary Guard Corps (IRGC) must be designated as a terrorist entity in Canada. This measure can be taken unilaterally, and would have a real impact on the ability of the IRGC to finance and train terrorist groups like Hamas, Hezbollah, and al-Qaeda; to torture and murder its own citizens; and to participate in business activities that financially benefit the regime.

Fourth, Canada and all Western countries need to fortify their energy security. Iran has threatened to close off the Strait of Hormuz, a critical passageway for much of the world's seaborne oil. The Harper government has rightly tried to convey the message that stable Canadian resources are an essential component of any solution to American and Asian energy needs.

At the same time, Canada needs to consider its own energy security in a more serious way. While its oil exports are substantial, Canada depends in part on Middle Eastern oil for domestic consumption. It may now be appropriate for the government to develop strategic petroleum reserves for its own residents, and diminish the salience of any Iranian threat to cut off the Strait of Hormuz.

In a move that seemed highly improbable a year ago, the European Union has committed to an Iranian oil embargo in hopes of compelling Iran to rethink its nuclear activities. This is a clear indication of the seriousness with which they perceive the Iranian threat. Canada has given every indication that it shares that bleak assessment. Now is the time to implement the above recommendations and take bold but responsible action in protecting the world from a nuclear-armed -- or even a nuclear-capable -- Iran.