New Delhi, Jan. 5 -- US President Donald Trump's new National Security Strategy offers a misguided assessment of Europe, long regarded as America's most reliable ally. Unrestrained immigration and other policies derided by administration officials as "woke," it warns, could lead to "civilizational erasure" within a few decades.

That argument rests on a basic misreading of Europe's current predicament. While the EU does face an existential threat, it has little to do with immigration or cultural politics. In fact, the share of foreign-born residents in the US is slightly higher than in Europe.

The threat facing Europe lies in its economic and technological backwardness. Between 2008 and 2023, GDP rose by 87% in the US, compared to just 1...