Kostenko has stated that he had a desire to join the military from a young age, and has noted that this was despite the fact that none of his family members other than his great-grandfather had previously served in military roles. At the age of 16, he decided to join the Odesa Military Academy, after also considering Sumy High Artillery Command School [uk] and Ivan Bohun Military High School.[2]
Military career
Kostenko's military career began in 2000.[1] He originally served in the 79th Air Assault Brigade, at first as a platoon commander, and later as a company commander.[3] In 2008, Kostenko moved from the 79th Air Assault Brigade to the Alpha Group, within the Security Service of Ukraine, in spite of his parents' protests and the lower pay.[2]
War in Donbas (2014–2022)
During the early stages of the war in Donbas, Kostenko chose to fight the separatist forces of the Donetsk People's Republic, using vacation days he had saved up to go to the front with the 79th Air Assault Brigade, his former unit.[2] In 2022, Kostenko said that he had joined the war "to restore justice", also saying:
When I was at Donetsk Airport for the first time, I was afraid that if I died, my family would not receive payments. I told everyone that I was going on vacation, and I took a machine gun and went to the front, because my unit was there - the 79th brigade, in which I served, and the "Alfa" [Group].
Kostenko was part of the group of Ukrainian soldiers known as "Cyborgs" for their defence of Donetsk International Airport during the Second Battle of Donetsk Airport. For this, he was awarded the Order of Bohdan Khmelnytsky in 2014.[4] Kostenko noted that many of the Cyborgs were not professional soldiers. He additionally criticised the attitude of some soldiers who did not fight at Donetsk Airport for that reason, saying, "Look, people don't know anything. Only that this is their land. They take a machine gun, and go and protect it. These people were the most motivated. When you see that you have such soldiers, there's no fear."[5]
Kostenko continued to serve in active duty until May 2019, retiring from active duty due to his election to the Verkhovna Rada (Ukraine's parliament).[6]
2022 Russian invasion of Ukraine
In 2022, immediately following Russia's invasion of Ukraine, Kostenko returned to active duty, travelling south to fight Russian soldiers attacking the city of Mykolaiv. Kostenko worked with Dmytro Marchenko to formulate the ultimately-successful plan to defend the city.[1] Kostenko led an ad-hoc special forces group that destroyed the bridges over irrigation channels around the city, helping to halt the Russian advance.[7]
Kostenko has been regarded as one of the most significant Ukrainian military commanders of the invasion, being listed by influential magazine NV [uk] as among the top 25 commanders due to his role in the Southern Ukraine campaign.[8] On August 12, 2024, Kostenko posted a video where he stood at a border checkpoint, with the sign "Russia" visible behind him. In the video, he humorously stated that he had entered the Kursk Region of the Russian Federation without a business trip, promising Verkhovna Rada Speaker Ruslan Stefanchuk that he would issue one later.[9]
In July 2019, in a 2019 interview to the Tsensor.NET website, Kostenko announced he was joining the Holos party, campaigning on a policy of bringing an end to the Russo-Ukrainian War and making Ukraine a "successful and comfortable country for life." He additionally cited the lack of victory in the war as the justification for his joining politics, and refused to rule out the possibility of becoming Minister of Defense. He additionally criticised the political establishment and welcomed anti-establishment figures as a break from what he referred to as the "political elite."[2]
Kostenko was placed 14th on the party list of Holos during the election, and was ultimately successfully elected into the Verkhovna Rada.[11] Following his election, he became secretary of the Parliamentary Committee on National Security, Defense, and Intelligence.[6]
Kostenko was the author of the successful Draft Law on Amendments to the Law of Ukraine "On the Foundations of National Resistance," which expanded the scope of Territorial Defense Forces operations.[13][14]