Is It Legal to Join Ukraine’s Military Defense?

Ukraine’s courageous fight against an invading foe eight times its size has captured many hearts.

It has prompted many of us to pray for peace or to contribute to refugee relief efforts. But for some of us, including many Americans, it’s stirred a desire to join the fight.

Following Russia’s invasion in late February, Ukrainian President Volodymyr Zelensky created the “International Legion of Territorial Defense of Ukraine” and invited foreigners to join it. Within a few days, Zelensky claimed 16,000 foreigners were on the way.

Realizing that not all volunteers are really cut out for combat, however, Ukrainian military officials also stressed that they do not want volunteers who lack military experience. Those who want to join the Legion must provide documents confirming military service and participation in combat.

The Law Governing Foreign Fighters

Before we start counting how many volunteer American boots might be on Ukrainian ground in the near future, it may be useful to look at the legality of leaving home to fight for another country.

First and most importantly, it is legal.

According to the U.S. State Department, U.S. citizens can join another country’s military. You can’t be recruited or hired within the U.S. to serve in another country’s military, but they can travel to that country to join the military or apply through that country’s embassy in the person’s home country.

According to the Defense Department, volunteer soldiers lose their own neutral status when they join a foreign military – not the neutral status of the country they’re from. This means that an American volunteer can at least be technically assured that they won’t be dragging the U.S. or NATO into the war by their presence.

Warnings to Stay Home

While volunteering to fight for Ukraine is legal, the U.S. Defense Department is discouraging Americans from doing it. In a March 11 press briefing, a senior military official said, “If a veteran or any other American citizen wants to support the people of Ukraine, the best way to do that is to donate to the Red Cross or any other humanitarian organization that’s trying to put together aid and assistance for Ukrainians. It is not to go into Ukraine.”

The Brookings Institute sounded a similar note, contending that foreign fighters can make things worse due to language issues. Furthermore, research suggests that violence involving civilians tends to increase when foreign fighters deploy. “In general,” the Institute said, “private war is a bad idea even in cases like Ukraine, when there is a clear victim state and villain state.”

Steps for Volunteer Fighters

Nevertheless, Ukraine has put out the call for help. For those who want to answer the call, Ukraine’s International Legion provides a list of necessary steps aspiring foreign fighters should follow. Here are a few:

  • Apply at the Ukrainian embassy by email, phone, or in person.
  • Identify the documents that will be necessary to prove military experience.
  • Prepare for a Zoom interview at the embassy and submission of an application.

Those accepted must then take more steps, including:

  • If possible, bring your own military kit, including helmet and body armor. Guns, however, should stay behind. Ukraine provides weaponry.
  • Get instructions on how to travel to Ukraine and the documents you will need.

Note: We are in no way endorsing that you do this.

Heightened Risks for Volunteer Fighters

Meanwhile, Russia issued a warning that foreign fighters — Russian President Vladimir Putin calls them “mercenaries” — will be treated harshly. On March 3, Russian Defense Ministry spokesman Igor Konashenko warned that foreign fighters will not be afforded the rights of lawful combatants under international law.

“At best, they can expect to be prosecuted as criminals,” he said. “We are urging all foreign citizens who may have plans to go and fight for Kyiv’s nationalist regime to think a dozen times before getting on the way.”

Still, thousands say they want to fight. By March 10, the Ukrainian Embassy in Washington, D.C., reported that it had heard from about 6,000 Americans. The embassy says it rejected at least half of them.