SEOUL, South Korea (AP) — North Korea ratified a major defense treaty with Russia stipulating mutual military aid, the North’s state media reported Tuesday, as the US, South Korea and Ukraine say North Korea has sent thousands of troops to Russia to support its war against Ukraine.

Nearly all would raise their hands to go, ex-military defectors explain, owing to regime loyalty, promise of higher status and a glimpse of the outside world.

The presence of North Korean soldiers alongside Russians fighting Ukraine raises many tactical and military questions, leading some analysts to wonder about their effectiveness and ultimate objectives.