Bitcoin will become the World Reserve Currency. Commodities and goods will be imported and exported with it. Governments cannot stop it. Banks cannot stop it. Nothing can stop bitcoin.
If governments make it illegal, people will bribe officials with it and come up with other ways to get around the law because it is too valuable. Bitcoin literally saves lives in some countries with hyperinflated currencies. When a government makes its currency worthless (hyperinflation) people turn to bitcoin to buy medicine for their family. This thing is not going away. Ever.
There is already too much money behind it in the US to make it illegal. Now that big financial money is involved, the corrupt politicians will not make it illegal. They will profit from it instead.
Even if governments shut down the internet and all electric power, people can download a bitcoin node from satellites in space for free make transactions for one penny US with text. They will get power from solar and other off the grid means.