Dear friend, You seems to be a person with lots of interest in History. You asked how few thousands muslim invaders could conquer lots of land. Well, the answer is simple. They were united, 1 by 1 they attacked every part and took advantage of the people's mutual fights in every country. At least that was what happened in India. A deeply cast based, divided society, where people were always fighting each other was an easy target for them. To add to it, invaders were savages (This can be clearly seen from Prithviraj-Gauri example, where Prithvi had shown human like treatment and Gauri later showed his animal nature). Anyway ... That is all past ... bad news is, even today we are not ready to learn from our mistakes. India is still a soft state (even in cases of national security). Our leaders are experts in cast politics. These days, all major political parties spending their 100% effort on UP elections. Previously they did the same for Punjab and Delhi elections. Soon other states will follow. So, in nut shell, we still are spending most of our effort in fighting with each other instead of cooperation. Its easy for anyone to target us.
