when both of them went to Krishna's tent then Arjuna sat at feet of Krishna and took his blessings but Duryodhana said "why is he sitting near feet of a cowherd boy " .
But Krishna is of everyone and everyone belongs to him so he is equal to everyone . When Krishna asked what they wanted ? Duryodhana said that he wanted Krishna's narayan sena (Krishna's soldiers) and when he asked Arjuna , he replied i want you with me and no one else . But Krishna told that he won't fight in war
Duryodhana thought with army he can easily win the War but we should be always in Krishna's team
Arjuna wanted to get the lost kingdom by himself.. He thought that his power was enough. Lord Krishna was not asked to fight war.