The announcement comes roughly five years after the military, which is formally known as the Tatmadaw, dramatically escalated its clampdown on the Muslim minority group. Over 1.2 million Rohingya have fled Buddhist-majority Myanmar since, and tens of thousands were killed.
Speaking at the US Holocaust Memorial Museum, Blinken announced just the eighth genocide determination in US history, saying the Tatmadaw carried out "widespread and systematic" attacks against the Rohingya, including the razing of villages, mass killings and rape, torture "and other horrific abuses."
Based on internal findings within the State Department and outside documentation from rights groups, Blinken said the evidence he reviewed "points to a clear intent behind these mass atrocities, the intent to destroy Rohingya, in a whole or in part."
That intent is corroborated not just by the accounts of former soldiers who defected, but also the military's very efforts to prevent Rohingya from escaping the systemic violence, Blinken said.
"This demonstrates the military’s intent went beyond ethnic cleansing to the actual destruction of Rohingya," the top diplomat said.
"Percentages, numbers, patterns, intent. These are critically important to reach the determination of genocide. But at the same time, we must remember that behind each of these numbers are countless individual acts of cruelty and inhumanity," he added.
Additional sanctions are expected to be applied under the US determination on the already heavily-blacklisted Myanmar junta.
The US determination comes as the UN's top court resumed in February its proceedings to determine if Myanmar is responsible for genocide.
The International Court of Justice (ICJ) has been hearing the case, which was brought by Gambia, and accuses Myanmar of violating the Genocide Convention in its brutal crackdown on the Rohingya community, for over two years.
Blinken said the US has provided Gambia with information to bolster its case, which he said is an effort to "lay the foundation for future accountability."
In January 2020, the ICJ imposed “provisional measures,” ordering the end to genocidal practices against the Rohingya.
Myanmar was being represented in the case by former State Councilor Aung San Suu Kyi, who was overthrown in the Tatmadaw's February 2021 coup, and has been jailed by the junta on various charges.
The military takeover has triggered mass protests in Myanmar in which junta forces have killed more than 1,500 people in a crackdown on dissent, according to the Assistance Association for Political Prisoners, a local monitoring group.
