In November, the US ambassador to the EU had warned that US President Donald Trump has "many, many other tools" to "curb and stop the project" if Berlin stayed adamant.
Less than a month later, Grenell told the far-right Breitbart news website that he saw his tasks as one of "empowering" Europe's right-wing governments and budding leaders. He also said that NATO members should back US interventions abroad.
The Federation of German Industry has said it's not bowing to increasing US pressure to drop the Russian-led Nord Stream 2 gas pipeline and buy US liquefied gas instead. The BDI adds it wouldn't make economic sense.
Russia, Ukraine, gas empires, Manafort and Breitbart! Is this what's behind it all?