One is that we can only consider a verse to have abrogated...

One is that we can only consider a verse to have abrogated another when it is incompatible with it. Imagine a verse being revealed commanding not to fight the polytheists at all followed by another allowing for fight. Good. This would mean that God has canceled the previous instruction. This is the meaning of abrogation, that the first instruction is annulled and replaced by another. So the second instruction must be such that it is fully incompatible with the first.

However, if collectively, the contents of the first verse and the second one are compatible, so that one clarifies the other, then there is no further question of one being an abrogator and the other being abrogated. The verses of Surah at-Tawba are not such that they can be said to have been revealed so as to nullify the previously revealed ones, which attached conditions to jihad. Why not?

Because, when we consider all the verses of Surah at-Tawba collectively, we see that they tell us to fight the polytheists because they do not observe one of the essential principles of humanity - keeping one's promises - which one and all know, must be kept, even if the law of one's particular nation does not stress this duty or heed it at all.

Thus the verses tell us to fight, because if we conclude an agreement with them, whenever they see the opportunity to violate it, they would do so and strive to destroy and annihilate us. Here, what does reason tell us? If we know for sure that a nation intends to destroy us on the first opportunity, does reason tell us to wait for them to do so before we do anything about it? If we wait, they will destroy us.

In today's world, we may see a nation attacking another because of clear evidence that the other nation has made the decision to attack them, and when that nation attacks, the whole world will say that it is permissible, that they did the right thing.

No one would say that although they knew and had clear evidence that, for example, the enemy had the intention of attacking on a certain day, that they had no right to attack the enemy today, that they should have waited with folded arms for the enemy to attack and only then, should they have gone into action themselves.

The Qur’an in those same verses of Surah Bara'at (Tawbah), the most strict verses of the Qur’an, tells us: « How (can there be such a league), seeing that if they get an advantage over you, they respect not in you the ties either of kinship or of covenant?