Well, if you think of bitcoin to be a national currency or local currency like dollar euro which is got a physical substance then you r right. But you are wrong in sense by evaluating btc as the form of paper currency. Its an financial asset which got the quality of higher rate of liquidation.
And please make your self understand that its a virtual currency not the local or national or wont be ever.
BTC IS A CURRENCY BUT ITS VIRTUAL AND YES EVERY CURRENCY IS A FINANCIAL ASSETS BUT EVERY FINANCIAL ASSETS ARENT THE CURRENCY.