5 countries that are impossible to conquer

Today, state security and sovereignty are one of the most important aspects for an independent country. Even though now, it is not that easy to conquer a state because of various reasons. In the past, states were conquered by other countries after a prolonged session of wars and fights. But now, the strength of the country is not dependent on its size, rather is dependent on economic strength.
However, as we said sovereignty and defense are a priority. We often think which states are the most sovereign and cannot be conquered by others. Here is a list of top 5 states that are impossible to conquer.

• The USA
• Russia
• China
• Switzerland
• 
  

— Afganisthan —