Which Southeast Asian country has a flag composed of horizontal red and white stripes, symbolizing courage and purity respectively?

Indonesia

The flag of Indonesia, nicknamed "Sang Saka Merah Putih" (the red and white treasure), consists of two simple horizontal stripes: red on top and white on the bottom. Adopted at the country's independence in 1945, this flag is inspired by the banner of the Majapahit kingdom in the 13th century. Red symbolizes human courage, while white represents spiritual purity. This flag embodies unity and simplicity, core values amidst the cultural and ethnic diversity of Indonesia, a country made up of thousands of islands and hundreds of different ethnic groups.