That's up to them and their own risk assessment. One thing I know for sure is that if they did, the US would wage an economic war so fiercely on Europe, that Nokia & Ericsson would have a tough time doing anything in the US for years to come.

Further, collateral damage would include all sorts of manufacturing, which would cripple Germany.

Remember the imbalance here: European manufacturing is more dependent upon the US than the US is on Europe. Fully 50% of Germany's GDP is exports, and worse, Germany exported $118bn of goods, while the US exported only $50 to Germany.[1] While that doesn't seem a big difference, once you look at it as a share of each other's economies, it is immense (roughly 3% of German GDP, versus only 0.5% of US GDP).

[1] - https://www.americanexpress.com/us/foreign-exchange/articles...