When in 1939 war did break out between Germany on the one hand, and Britain and France on the other, President Franklin D. Roosevelt dutifully invoked the Neutrality Acts. However, he believed that this was a fundamentally different war from World War I.
Another advanced coal technology is coal gasification, a process in which coal is converted to a gas (called syngas) before it is burned, making it easier to separate CO2 as a relatively pure gas before power is generated.
Coal is used primarily as an energy source, either for heat or electricity. It was once heavily used to heat homes and power locomotives and factories. Bituminous coal is also used to produce coke for making steel and other industrial process heating.