Peace
You know that surah 8: 12 is referring in the context of battle by the prvious verses:
8: 1
They ask you, [O Muhammad], about the bounties [of war]. Say, "The [decision concerning] bounties is for Allah and the Messenger." So fear Allah and amend that which is between you and obey Allah and His Messenger, if you should be believers.
8: 9
[Remember] when you asked help of your Lord, and He answered you, "Indeed, I will reinforce you with a thousand from the angels, following one another."
and the latter verses:
8: 15
O you who have believed, when you meet those who disbelieve advancing [for battle], do not turn to them your backs [in flight].
8: 16
And whoever turns his back to them on such a day, unless swerving [as a strategy] for war or joining [another] company, has certainly returned with anger [upon him] from Allah , and his refuge is Hell - and wretched is the destination.
You can see that for EVERY so-called "Jihad verse", Godhas clearly stated the context of battle.
Peace