>> Indian trains are pathetic.They run at 70-90 >> kmph.
Apply little stress on your Chicken brain - answer lies in your post!! Key is Design Speeds!! We don't have such design speeds.
To implement that we need to pump more than $100 billion (4,50,000 crores) for our tens of thousands of rail track!!
Why rail? Even on Roads, we don't have such design speeds. Safe design speeds on our Roads won't be more than 100 Kmph compared to World's best roads (Autobahns in Germany)has 200 Kmph!!!