Question: The following verse shows that the ruler of an Islamic state has the power to veto his confidants if he deems so. 

So ignore their faults and ask for God’s forgiveness for them and consult them in the affairs [of state]. Then, when you have taken a decision, put your trust in Allah. (3:159)

    Please comment.

    Answer: I am afraid this is an incorrect inference. Needless to say that the Qur’an is a coherent Book. Each verse has a specific context, disregarding which may lead to gross misinterpretation. 
    If we take a look at the context of 3:159, it becomes evident that the verse occurs in the group of verses in which the behaviour of the hypocrites and the events of the battle of Uhud and their aftermath are under discussion. The hypocrites, we know from the Qur’an, were given a time of respite so that they might reform themselves. However, once the time was over, they were severely dealt with as is evident from many verses of the Qur’an. For example:

O Prophet! Strive hard against the Unbelievers and the Hypocrites, and be firm against them. Their abode is Hell, -- an evil refuge indeed. (66:9)

    The battle of Uhud was the time when they were still in the period of respite. So, it was not appropriate to disregard them at that time. Consequently, the Prophet (sws) is told to keep consulting them in various affairs; however, he is not bound by what their majority says. If he decides contrarily, he should repose his trust in Allah and do what he has decided. This is a brief summary of the stress of the verse. 
    A more detailed look at the context of 3:159 and at the various historical facts shows that the Prophet (sws) had consulted the Muslims on whether they should fight the enemy from within the city or from the outside. The hypocrites opined that they should fight from within the city while the true believers were of the opposite opinion. The Prophet (sws) it seems also held the latter opinion. So when he and the believers decided to go out and fight, the hypocrites became angry and expressed their anger in various ways. Abdullah Ibn Ubayi for example departed right before the battle with his three hundred men saying that his opinion was ignored. Another group of the hypocrites that stayed with the Muslims started spreading the propaganda once the battle was over that the defeat was due to the wrong strategy adopted. Consequently, 3:156-8, while addressing the hypocrites^*, mention these details in the following manner: 

O you who believe, be not like the unbelievers who say of their brethren when they are travelling through the land or fighting: ‘If they had stayed with us they would not have died or been slain’ so that Allah may make a cause of regret in their hearts. It is Allah Who gives life and death. And Allah knows what you do. And if you are killed or die in the way of Allah, forgiveness and mercy from Allah are far better than all they amass [of worldly wealth]. And whether you die are or killed, verily, unto Allah you shall be gathered. Had you been severe or harsh, they would have broken away from you. (3:156-8)

    Consequently, it is clear from these verses that the Prophet in (sws) his capacity of a Prophet (sws) was advised to deal with the hypocrites of his times in a particular manner, as spelled out in the subsequent verse; in other words, this subsequent verse also like the previous ones refers to the hypocrites: 

So ignore their faults and ask for God’s forgiveness for them and consult them in affairs. Then, when you have taken a decision, put your trust in Allah. (3:159)

    These verses cannot be related to us in any way today. Technically speaking, the antecedent of the plural accusative pronoun in the imperative verb shawirhum are the hypocrites of the Prophets times. Owing to his position as Prophet, Muhammad (sws) was divinely guided in their affairs and was told to deal with them with latitude until the Almighty signalled to him that the period of respite was over. 
    Consequently, the verse cannot be extended to anyone beyond the Prophet (sws).