A Brief Note on S 2:154

S 2:154 And do not say of him killed in the way of Allah: Dead men. Rather, alive, but you do not perceive.

The jihadi killed while performing an act of terrorism is not be considered as dead as a crushed insect but it is to be understood that he is still conscious, but you don't perceive him. How might one perceive a man who has died? Is he among people as a ghost? But aren't dead terrorists supposedly in the Jannah in a green bird?

Narrated Abdullah ibn Abbas:

The Prophet (ﷺ) said: When your brethren were smitten at the battle of Uhud, Allah put their spirits in the crops of green birds which go down to the rivers of Paradise, eat its fruit and nestle in lamps of gold in the shade of the Throne. Then when they experienced the sweetness of their food, drink and rest, they asked: Who will tell our brethren about us that we are alive in Paradise provided with provision, in order that they might not be disinterested in jihad and recoil in war? Allah Most High said: I shall tell them about you; so Allah sent down; "And do not consider those who have been killed in Allah's path." till the end of the verse.

https://sunnah.com/abudawud:2520

Might they be flitting around as such on Earth and when you see a green bird it may be a terrorist?

Further reading: Dead but not Dead