Tillerson was a businessman, and as such, he has to always stay within the realm of the doable. You notice he does not like to talk to the Fake News press or hold news conferences with those who are incapable of accepting the truth. Instead, he deals with the leaders of the various countries, leaders who can make practical decisions that affect the outcome, hopefully one that he seeks. There is no theory of diplomacy with Tillerson. There is always and only the praxis of the possible in facing every problem posed to the country. In this sense, he will be successful where the bigotry or arrogance of others will fail them. Nothing is more persuasive than humility coupled with strength and intelligence.