Why rich countries are rich?

Rich countries are rich because they have good political leaders that can get great decisions without hesitating. Not only that, but their people also gathered to develop their countries. But some countries like United Kingdom developed their countries by collecting resources by invading other countries. Countries like United States sold weapons during world wars and by using that money they became very powerful. Some countries have so many valuable resources like fuel and gold. So, they became very powerful by selling those resources. But there are some countries like Singapore who have created their own economy by tourism. Big countries like India and China using their manpower and political tricks to grow their economy by capturing other countries economy slowly. Likewise, most countries have their own system to develop their countries. But countries like Sri Lanka that have a corrupted government and corrupted politicians selling their resources to rich countries. Because of those rich countries will become more developed and poor countries will become very poor. After some time, poor countries will never be able to develop their countries. That’s why rich countries remain rich and poor countries remain poor.