Just something to add here. Only country determined in the West to invade us currently is UK due to fact we see them as an existential threat just like USA did in its early years of independence.
Of course if Portuguese, Dutch, French, German and even Danish see an opening they will not hesitate to attack us
Their zeal to invade is not to steal our wealth, but to eradicate and replace our population with themselves
Examples- New Zealand, Australia and USA
India is best piece of real estate on the planet when it comes to sustaining human population. Unlike US and China we can even grow crops in the winter
Colonial powers are cursed with lands that cannot sustain their populations, even today UK imports 48% of all its food
https://www.foodsecurity.ac.uk/challenge/uk-threat/
What will ultimately determine our safety is our ability to bring war to London, Lisbon, Paris, Berlin, Amsterdam and Copenhagen etc
Best defence against invaders is extinction and genocide of invader
Russians have followed this policy and it has worked wonders for them.
Turks were invading and enslaving Slavs as early as 3rd century. Russians responded by genociding them, Rusification and using invader's lands as buffer against any potential future invaders.
Demographics will not be of any consequence because
- Pakistan, Bangladesh, Sri Lanka and other traitors within our subcontinent willing to collaborate with British or any external invader and compensate for numbers.
- Potential of small cheap drones is replacing the need for boots on ground
- The threat of successful biological warfare attack can significantly reduce our demograhic advantage.
When colonial British attacked us we had the upper hand in demographics, economy and even in technology in some cases(Mysore rockets, better quality ships)
Only thing we lacked was war of offence. No Maratha, Mughal, Sikh ever made a goal to target London and hence British outlived each of one of these empire. All British needed was one victory vs Indians needing to defend successfully each time.