If Suryadeva can provide invincible kavacha kundala to Krana,

If Suryadeva can provide invincible kavacha kundala to Krana, is it difficult for Krishna to provide the same to Arjuna? In case, if Krishna had provided same to Arjuna what would be the consequences? He was given a divine armor by Indra when he visited heaven. Further, Armor of karna doesn't make him invincible, just saved him from death. Arjuna doesn't need that protection. Throughout the war Krishna saved him multiple times. Krishna to Yudhisthira : After I had arrived at Upaplavya, thyself, approaching me, with the wielder of gandiva in thy company, gavest me honey and the customary ingredients, and saidst these words, O Lord: 'This Dhananjaya, O Krishna, is thy brother and friend! He should, therefore, be protected by thee in all dangers!' After thou didst say these words, I answered thee, saying, 'So be it!' That Savyasaci hath been protected by me. Victory also hath been thine, O king! With his brothers, O king of kings, that hero of true prowess hath come out of this dreadful battle, so destructive of heroes, with life!' Thus addressed by Krishna, King Yudhishthira the just, with hair standing on end, O monarch, said these words unto Janardana: Yudhishthira said, "Who else save thee, O grinder of foes, not excepting the thunder-wielding Purandara himself, could have withstood the brahmastras hurled by Drona and Karna! It was through thy grace that the samsaptakas were vanquished! It was through thy grace that Partha had never to turn back from even the fiercest of encounters! Similarly, it was through thy grace, O mighty-armed one, that I myself, with my posterity, have, by accomplishing diverse acts one after another, obtained the auspicious end of prowess and energy! At Upaplavya, the great rishi Krishna-Dvaipayana told me that thither is Krishna where righteousness is, and thither is victory where Krishna is!'" Moreover even if someone were to kill him, the divine forces of nature would prevent it from happening. During Ashwamedha of Yudhisthira, Arjuna was about to be killed by Jayadratha's soldiers in their battle, but Saptarishis saved his life as his PURPOSE wasn't fulfilled yet. When his life was at risk because of his vow to either kill Jayadratha or commit suicide, Shiva aided him in fulfilling this vow on the 14th day.