If they got the position by working their way up through the foreign service (not all do) they know the history, the people, the culture, the issues, the language, and have relationships in the region that they can leverage when needed.
Then are they still effective now in 2018? and if so in what? I mean for example private busineses usually have sales reps, contracted in the country in which to do business. No embassy gets involved normally. This sort of job could be privatized as well, hire on the ground consultants and give jobs locally as needed. I know the CIA does it anyway. Locals, just like sales reps.
Meddling in other governments has caused so much war, fighting and other problems. Right? The US imposing our capitalism around the world hasnโt been successful, otherwise all these illegal immigrants would prefer to stay in their home country. Inequality and Caste systems still exist and wonโt go away. Foreign interventions post WW2 are to me almost all total failures. Maybe Kuwait and the UN in former Yugoslavia but that was combined EU work. Failures like Vietnam, Iraq, Afghanistan (sadly is dragging on forever, I recall the Soviet occupation days). Now Syria.
Now all the EU pushback on the FANG. Thats simple, the EU does their own censoring at their own discretion and expense. If this Khan does not like it, well they can censor it themselves.
Look at our own hemisphere in Latin America, United Fruit exploitation, overthrown Allende, what impact were ambassadors in argentinas dirty war? They ran away asaik. Then the bungling of the Bush takeover of Iraq.
I think you know that I represent a low budget, hands off approach, small govt, small business just the opposite of these messes we get in. I go overboard on the isolationism thing, but agree with the America first program, but remain skeptical. Disruption is the new clicheโ word, so disrupting traditional government seems to be advantageous to me as a taxpayer. My 2 cents.