What is the reason why Su Wu insists on honesty?

Su Wu's national integrity of never serving his country, honoring his mission and being loyal to the Han Dynasty embodies his strong national consciousness and patriotic integrity. Su Wu's persistent spirit of not being overwhelmed by power, not being confused by wealth and unyielding death shows his unique quality of putting life and death at risk and treating wealth like dirt. Su Wu's courage to survive against the harsh environment for many years shows his tenacious will and perseverance. Khan just wanted to use the sinister environment of ice and snow, biting cold and loneliness to destroy Su Wu's will and make him surrender. However, Su Wu just stood down with a very firm belief in his heart. With nothing, Su Wu survived. Moreover, it lasted 19 years. Su Wu's indomitable quality stems from the indomitable and hard-working great national spirit of our Chinese nation. It is this spirit that makes him a giant in the history of China, and also makes future generations remember and praise him forever.