OTTAWA — Canadian politicians and human rights advocates are voicing unusually sharp condemnation of the Trump administration after a deadly boat strike off the coast of Venezuela, accusing Washington of crossing a moral and legal line and warning that accountability for alleged war crimes will eventually arrive — even if it takes decades.

The backlash has been led most prominently by Charlie Angus, a longtime Canadian lawmaker and prominent commentator with the progressive outlet Midas Canada, who has framed the incident as part of a broader “age of gangsters” in global politics.

“These extrajudicial killings are very serious. These are war crimes,” Mr. Angus said in a recent video commentary, arguing that the operation violated not only international humanitarian law but also the United States’ own military code. He was referring to reports that U.S. forces struck a suspected narco-trafficking vessel and then carried out a second strike on survivors clinging to wreckage in the water.

What has particularly inflamed opinion north of the border is not only the alleged conduct at sea, but how it has been publicly presented. Mr. Angus singled out Defense Secretary Pete Hegseth, accusing him of trivializing the violence by circulating a cartoon depicting “Franklin,” a beloved Canadian children’s turtle character, as a grinning killer dispatching defenseless people.

“Franklin teaches kids how to be nice and how to be good neighbors,” Mr. Angus said. “And instead, Hegseth turns Franklin into this happy murderous killer. It’s about dehumanizing our enemy. It’s about embracing cruelty and laughing at breaches of international law.”

Mr. Hegseth has defended the strikes as lawful acts of self-defense against “narco terrorists,” according to prior public statements, and administration officials have said they acted under existing authorities to protect American interests. Rights advocates and several lawmakers, however, have pressed for more transparency, including the release of unedited video from the operation and a clear articulation of the legal basis for the use of force.

The Pentagon’s own Law of War manual, Mr. Angus noted, explicitly states that individuals incapacitated by wounds, sickness or shipwreck are hors de combat — out of the fight — and must not be made the object of attack. “Persons who have been incapacitated … are in a helpless state, and it would be dishonorable and inhumane to make them the object of attack,” the manual says.

The controversy has also rekindled debate about Canada’s historical role in shaping modern war-crimes norms. Mr. Angus invoked the 1918 sinking of the Canadian hospital ship Llandovery Castle by a German U-boat off the coast of Ireland. After torpedoing the vessel, the submarine’s crew reportedly rammed lifeboats and machine-gunned survivors, killing doctors, nurses and sailors.

Outrage over the Llandovery Castle helped drive early efforts to codify protections for shipwrecked and wounded combatants. “Those with the guns don’t get to shoot those without guns on the high seas,” Mr. Angus said. “That’s the path Canada set itself on, and we’ve never U-turned away from it.”

For critics of the Trump administration, the reported Venezuela strike fits a broader pattern of what they see as the normalization — and even celebration — of extreme violence. Mr. Angus drew explicit parallels to Russian operations in Ukraine and Israeli conduct in Gaza, citing widely publicized allegations of civilian killings. He recounted the case of a six-year-old Palestinian girl, Hinn Rajab, whose killing has been the subject of international scrutiny, calling it one of the events that “literally made me rethink everything I thought about the world.”

Supporters of the administration reject such comparisons as inflammatory and politically motivated, arguing that U.S. forces are targeting transnational criminal organizations that move drugs toward American shores and that commanders are making split-second decisions in dangerous environments. They also note that inquiries into alleged misconduct by militaries worldwide are often lengthy, complex and heavily contested.

The debate has exposed divisions within Canada’s own political establishment. Anita Anand, Canada’s foreign affairs minister, drew criticism from Mr. Angus after she suggested early in the controversy that it was up to the United States to determine whether its actions breached international law.

“In what world would you say the perpetrator of the crimes gets to decide whether those crimes are crimes?” Mr. Angus asked, calling the remark “outrageously dumb” and urging Ottawa to reassert its traditional support for independent war-crimes investigations. Canada is a state party to the Rome Statute, which established the International Criminal Court.

Investigative reporting has added to the pressure. According to Mr. Angus, a recent analysis by The Intercept raised questions about Mr. Hegseth’s role and suggested that the entire chain of command could face scrutiny for possible war-crimes liability — an assertion that U.S. officials have not publicly addressed in detail.

For now, much of the dispute remains in the realm of competing narratives: an administration insisting it is waging a necessary campaign against dangerous traffickers at sea, and critics in Canada and beyond warning that the line between law enforcement and unlawful killing has been dangerously blurred.

What unites many of those critics is a sense that the public is being slowly desensitized. “It’s not just about the war crime,” Mr. Angus said. “It’s about trying to make us go along, to think it’s okay.” He warned that if such actions go unchallenged — whether in Venezuela, Gaza, Ukraine or elsewhere — the world risks sliding deeper into what he called “an age of monsters.”

“There has to be accountability,” he said. “Otherwise we go into a very, very dark place.”