Allah tells us how ignorant the idolators are; instead of worshipping Allah, they worship idols which do not possess the power either to harm or benefit. They do this with no evidence or proof; the only thing that led them to do this was their own whims and desires. So they take these idols as protectors and fight for their sake, and they oppose Allah and His Messenger and the believers for their sake. Similarly Allah says:

[وَكَانَ الْكَـفِرُ عَلَى رَبِّهِ ظَهِيراً]

(and the disbeliever is ever a helper against his Lord.) meaning, he is a supporter of Shaytan against the party of Allah, but the party of Allah are the ones who will prevail, as Allah says:

[وَاتَّخَذُواْ مِن دُونِ اللَّهِ ءَالِهَةً لَّعَلَّهُمْ يُنصَرُونَ - لاَ يَسْتَطِيعُونَ نَصْرَهُمْ وَهُمْ لَهُمْ جُندٌ مٌّحْضَرُونَ ]

(And they have taken besides Allah gods, hoping that they might be helped. They cannot help them, but they will be brought forward as a troop against those who worshipped them.) (36:74-75) meaning, the gods which they worshipped instead of Allah cannot help them. These ignorant people are troops for the idols and are ready to fight for their sake and protect their sanctuaries, but in the end the victory will be for Allah and His Messenger and the believers, in this world and the Hereafter.

[وَكَانَ الْكَـفِرُ عَلَى رَبِّهِ ظَهِيراً]

(and the disbeliever is ever a helper against his Lord. ) Mujahid said: "He supports and helps the Shaytan in disobedience towards Allah.