Kingdom of Bhutan (modern, standardized flag)
Who & why: under the third and fourth Druk Gyalpos, Jigme Dorji Wangchuck and Jigme Singye Wangchuck, Bhutan opens cautiously to the outside world — joining the UN in 1971, ending its self-imposed isolation in stages, and modernizing its institutions while carefully guarding its own culture and sovereignty. Somewhere in this stretch (commonly dated to the late 1960s, with the exact year debated among sources) the national flag's design, proportions, and colors are fixed into the form still flown today.
What it represents: the flag is split diagonally, yellow upper triangle (the secular authority of the Druk Gyalpo) over orange lower triangle (the Buddhist spiritual tradition and the Drukpa monastic bodies), with the white Druk, the Thunder Dragon, centered along the divide, clutching jewels that represent the nation's wealth and security. The dragon's snarling posture is read as guardianship, not aggression.