Ferhat Mehenni insulted the Algerian flag and this was an affront to all Algerian citizens.

“If a lady,” he said, “asked him any question upon the subject, he would neither answer her nor speak to her again while he lived; if a gentleman, he would consider it as a mortal affront, and demand satisfaction as having received such.”

Those who threatened the religious order were severely punished. The reason for this is, of course, obvious. The religious authorities gave the monarch divine right, and an affront to the religious establishment was a threat to the monarch's power.

It is too true, however disgraceful it may be to human nature, that nations in general will make war whenever they have a prospect of getting anything by it; nay, absolute monarchs will often make war when their nations are to get nothing by it, but for the purposes and objects merely personal, such as thirst for military glory, revenge for personal affronts, ambition, or private compacts to aggrandize or support their particular families or partisans. These and a variety of other motives, which affect only the mind of the sovereign, often lead him to engage in wars not sanctified by justice or the voice and interests of his people.

Yanni took that as a personal affront.

O Muse, assist me and inspire my song, / the various causes and the crimes relate, / for what affronted majesty, what wrong / to injured Godhead, what offence so great / Heaven's Queen resenting, with remorseless hate, / could one renowned for piety compel / to brave such troubles, and endure the weight / of toils so many and so huge. O tell / how can in heavenly minds such fierce resentment dwell?