It’s 2013 and the Southern Ocean remains vast and unforgiving—a cold, wild expanse where the horizon blurs into endless grey water. Somewhere among the waves, a lone whale surfaces, exhaling a plume of mist into the frozen air. As mighty as a mountain, as defenceless as a lost child; in the distance, the dull hum of engines draws closer. It’s not the sound of rescue or sanctuary, it’s a harpoon ship, bearing down fast. Before it can take aim, another vessel barrels between predator and prey. The Bob Barker, black-flagged and relentless, cuts across the whaler’s path, its crew shouting warnings through the freezing wind. They’ve crossed a line, both legally and physically, but to them, it’s the only line that matters.
For Sea Shepherd, these moments define the moral battleground they navigate. When governments fail to enforce conservation laws and protected species continue to be hunted under the guise of “science”, waiting for bureaucratic solutions feels like complicity.
“If we don’t act, the whales die,” says Kelly Dinham, a spokesperson for the marine conservation group. “The law should protect the ocean, but when it doesn’t, we step in.”
Sea Shepherd’s history is full of bold operations. In 2010, their fleet pursued the Japanese whaling vessel Shonan Maru 2 in Antarctic waters. A high-speed catamaran, the Ady Gil, joined the chase, cutting dangerously close to the whaling ship’s path. When the two vessels collided, the Ady Gil sank into the frigid ocean. The sight of the half-submerged vessel drifting away became a symbol of both the group’s audacity and the risks they face.
Over the years, the organisation’s missions have grown more ambitious. They’ve rammed whaling vessels, boarded ships, fouled propellers with ropes and thrown butyric acid onto whaling ships’ decks to taint whale meat and render it unfit for sale. On top of that, Sea Shepherd publicly claims to have sunk 10 ships.
They believe that killing whales is intrinsically wrong, so teleologically to stop the Japanese, their strategies are justified.
But the stake of such direct action raises further ethical discussion.
Can violence be justified if it saves lives?
Can harm be excused if it prevents greater harm?
One ethical argument suggests that direct action may use violence on some occasions. The use of violence should be directly targeted at the wrongdoing and limited to situations where activists sincerely and reasonably believe there to be no feasible alternative route to the prevention of wrongdoing. This purposeful use of violence allows direct action to be used in a constrained way, such that it remains recognisably distinct from guerrilla warfare or political terrorism.
But why not engage in deliberative democracy instead?
According to Sea Shepherd, the gravity of a wrong that is genuine, serious and urgent, like that of Japanese whaling, warrants the degree of violence or vigilantism that is employed within a direct action campaign.
While direct action typically does not aim to promote discussion, it can attract significant attention insofar as it is creative, theatrical and confrontational.
Take Blockade Australia for example. In June 2023, activist Brad Homewood glued himself to a nine-metre pole, blocking Appleton Dock in Melbourne and the incoming coal imports for hours. “This is the economic core of the problem,” Homewood explained. “We disrupt trade to make people understand that the system as it stands is unsustainable.”
In 2022, the organisation staged a dramatic protest at Sydney’s Port Botany. Activists scaled shipping cranes and dangled from ropes high above the ground, halting operations for hours. The scene was tense. Police swarmed the site, workers stood by in frustration and helicopters circled overhead. Although many were eventually arrested, the activists saw it as a victory as their campaign was plastered all over international media.
The challenge lies in balancing disruption with public support. Successful direct action campaigns have shown that change often requires making people uncomfortable. However, they also reveal the need for broad-based support to sustain a movement. Direct action risks bringing the whole movement into disrepute. This can be through associating their cause with violence or terrorism and reducing the scope for mainstream activism to receive a hearing in the public sphere.
Direct action need not always involve confrontation with violence or property damage. Such as the largely non-violent protests of the American Civil Rights movement of the 1960s. Sometimes, creating moral theatre, forcing the public to confront an inconvenient truth, can be enough. Yet Sea Shepherd’s defenders argue that the scale of environmental collapse demands more than symbolic acts. “When the oceans are dying, there’s no time for half-measures,” Dinham insists. “Our actions speak louder than words.”
“There are risks on both sides.”
“Yes, bold action might alienate some people. But inaction carries greater risks. The oceans are dying, we don’t have time to be polite.”
Blockade Australia echoes this sentiment. Homewood, who has been arrested 13 times for his activism, believes the stakes are too high for half-measures. “The collapse of ecosystems means the collapse of society,” he argues. “How can anyone stand by and do nothing?”
The question, then, is not whether disruption is justified but whether it is enough.
Many opposers of Sea Shepherd describe them as ‘eco-terrorists’. Japan continues to condemn Sea Shepherd as a terrorist organisation and has issued warrants for the arrest of Captain Paul Watson and others after he rammed and sunk the whaling ship Sierra. Whether or not the destruction of property constitutes terrorism, it still violates legal and moral rights. Sea Shepherd’s tactics remain controversial, even among those who support their cause. Although the group claims to operate under guidelines that avoid unnecessary harm, critics warn that reckless actions can spiral into extremism.
Blockade Australia faces similar scrutiny. Their protests have led to arrests, fines and public backlash. In one instance, an activist was dragged from a road blockade by angry commuters. “We must raise the alarm, even if that means breaking the law,” Homewood insists.
So, at what point does direct action become too dangerous for it to be justified?
Consider the case of Greenpeace’s Rainbow Warrior, an example where activism crossed a boundary with devastating consequences. In 1985, the Rainbow Warrior, a vessel used to protest French nuclear testing in the Pacific, was sunk by French intelligence agents while docked in New Zealand. The agents planted explosives that tore through the ship’s hull, killing crew member Fernando Pereira.
Unlike Sea Shepherd, Greenpeace did not engage in confrontational tactics, yet their disruption was seen as enough of a threat to warrant violent repression. The sinking reminds us that direct action can provoke powerful opposition, making the stakes higher not only for activists but also for those around them. This is a sobering reality. When activists escalate their actions, their opponents can respond just as unpredictably.
Sea Shepherd, Blockade Australia, and the case of the Rainbow Warrior, ask whether direct action is only reasonable when it stays in certain limits.
The answer lies in delicate tension. Reasonable, in this context, is not measured by politeness or conformity to law, but by the moral urgency of the crisis at hand. Direct action, like that of Sea Shepherd or Blockade Australia, is not inherently unreasonable, nor is it inherently justified. Instead, it must be judged by the stakes it confronts and the outcomes it aims to achieve.
But direct action, however bold, must also carry accountability. There is a fine line between necessary disruption and reckless escalation. Crossing it risks alienating the very support these movements need to succeed. The challenge for activists, then, is not only to act but to act wisely, choosing tactics that amplify their cause without undermining it.
“For young activists, we advise staying true to your mission while understanding that public accountability is essential. Bold action and transparency can coexist to inspire change without alienating those you seek to engage,” Dinham advises.
Today, Sea Shepherd continues its work unabated. In Antarctica, The Allankay hunts those seeking to disrupt the balance of the ocean’s ecosystem. They watch as supertrawlers plow through pods of whales, seals and penguins, taking their primary food source of krill for themselves. Sea Shepherd springs to action again.
At the far side of the Southern Ocean, traffic resumes at Melbourne’s port. Coal shipments begin again as Blockade Australia plans its next protest. Whether their actions are reasonable or reckless, one thing is certain—Sea Shepherd and Blockade Australia won’t stand by.
