1. There is relatively same climate in the two regions of the indian subcontinent and the eastern asia.
2. China has about 1.3 billion people and india ahas about 1.1 billion.
3. East asia is much open to invasion than the sub subcontinent.
Explanation:
The Indian and eastern Asia have relatively shared the same type of climatic regions and they have the same nature of the terrain and the lands thus have a similar topographic characteristic.
As the population of China is ahead of India and it continues to grow but the population of the Indian subcontinent also is expanding at a much faster rate and will overtake the china in the 2030 time period.
Due to the Himalayas acts as barriers in between the lands of the Indian subcontinents the invasion is not easy and as compared to that of eastern Asia.
