Does the presence of foreign departments within the company is the only guarantee for the success of this company in the Arab world?

Sure the answer is No.

You yourself are in a great position at your work do you think if they get a foreigner employee he would do a better job than you ? the answer is no you will do better if you want to.all you need is the right knowledge, skills and abilities in the employee with the proper motivation and mentoring no matter what's his nationality is.

not foreign departments but foreign people, of course skilled ones :) because they will teach Arabs how to be objective  and not mix professional matters with personal ones

Of course not and we have an excellent balance of skills and expertise that Arab unfortunately not well invested, Only the in the Western countries you can find them in the best universities and scientific and economic centers.

its better to keep those departments/people if the company wants to compete globally as it is the people who will bring ideas, skills and technology which will drive the company towards global success.

If companies have local pool of talent which is better than International workers there is surely no need.

But mostly Western countries are technology advanced countries so employees have hi -tech exposure which comes handy for companies.

Also it creates a global atmosphere in office and company has a global approach overall which creates reputation.

Well, to start with, it sounds more of a rhetoric question to me. I totally understand the precipitation of superiority/inferiority complexes deep within Middle Eastern cultures and business enivironments. However, there is NEVER a guarantee of success that is based merely on the race of the manager.

When super power countries like America/ Canada/ France/ Italy / Germany / China / Japan have foreign workforce why not the Arab world dont look at it as a foreign department there is no foreign department its all part of the organisation its only that each department has expatriate and local workforce the organisation or the company is local or even if it is a multinational it has local participation in ownership take America for example they have the best Doctors / Scientists/ IT professionals/ Software designers because they have the best from the rest of the world in these fields with them and why do these best work for American because they find comfort, they are paid well and taken care of with as a matter of fact America gives them nationality so they dont migrate to other countries this is the secret behind their success and the reason why they are a super power every country or region cannot build itself on its own the very existence of humanity is inter-dependent so is the existense and success of every nation in this world  what was India2 decades ago and today every major multinational wants to invest in India ?????????????  Why???????????