It doesn't much matter that Americans are the largest contributors, because you can still take it and change it however you want.
You can but the firmware that is needed to run it is American, because the hardware is American. Even if the company wants to open source it, the US government can block it in whatever country.
You can but the firmware that is needed to run it is American, because the hardware is American. Even if the company wants to open source it, the US government can block it in whatever country.