If the value of US Dollar crashed the economy of the entire world will also down as most of the countries depend on USD and their economy may also depend on bitcoin therefore if the USD crashed it will effect all most all the economies of the world.
Nope I do think so, because if we see the crises in US dollars it would affect the USA region only. I think other countries would be safe I'm their economic balance. I think USA government may adopt the bitcoin that time make as the national currency.
the impact of the currency fall only slightly to the economy of the country as a example GBP now is currently falling but the British economy is still pretty good and it will be same with usd if usd fall does not mean usa economic will collapse.