Large population can become a blessing for a nation when we could mould this large population to some important and profitable resource to become a profitable asset for the country. What I mean by moulding is to provide them some good jobs. If you take and example of country like India and look at Indian GDP, service sector is the only sector, which is showing a continuous double digit growth and is a major contributor to Indian GNP and this sector does not require much resources other than Human Capital, just the managers need more leadership skills to motivate and provide them proper direction.
But if you are not able to mould this large population in good assets as described above, all this turns into a curse.
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It is a curse believe it or not it is we will realize to sooner or later.
though it is very attractive as regards work force but when supply demand will collapse what to do with excess manpower????????????????