Perhaps the greatest driver for Islamic terrorism are massive casualties of Moslem civilians in the Middle East.
Trump greatly reduced the casualties from America’s decades-old wars. Biden is reversing that trend, which is likely to result in a return to levels of Islamic terrorist attacks from the Obama-Biden administration.
Of course, more terrorist attacks and more wars in the Middle East mean more military spending, more immigrants from the Middle East to Europe and the US, more warrantless surveillance, and more claims that “white supremacists are the greatest threat”. Never let a crisis go to waste!