The Arab League is the remnant of an empire and is one of the last remaining imperialist entities in the world. Dozens of non-Arab nations and tribes live under Arab rule, usually without their existence as peoples being acknowledged, often with no civil rights, and too often as slaves.
(http://citizenleauki.joeuser.com/article/342811/Sudanese_Refugees_in_Israel_Demonstrating_Against_Bashir)
(http://citizenleauki.joeuser.com/article/338699/The_Arab_Empire)
During the so-called decolonisation of the 1950s and 1960s and between the world wars European powers decided for some reason to hand over power over Berbers in North-Africa and black Africans in the Sudan, as well as Kurds and Assyrians in Syria and Iraq to Arab governments. This was considered "decolonisation" by the UN and essentially replaced the masters without freeing the slaves.
Since then the world has essentially ignored this vast empire and calls for "ending imperialism" are never directed at the Arabs, who rule over North-Africa and almost the entire middle east, but at Israel, the only non-Arab nation in the region not ruled by Arabs.
Only the Jews had a lobby powerful enough and only Israel became independent of Arab imperialism, but at a very high price. Israel and Jews are demonised all over the Arab world but enjoy considerably popularity among the other peoples ruled by the Arabs.
(http://citizenleauki.joeuser.com/article/337068/The_Arab_Empire)
(http://citizenleauki.joeuser.com/article/333584/Simon_Deng_Former_Slave_from_Sudan)
Note that this has nothing to do with Islam, as Islam does in no way demand Arab rule over other peoples and in fact the Quran doesn't speak too highly of the Arab people.
"The Arabs of the desert are the worst in unbelief and hypocrisy, and most fitted to be in ignorance of the command which Allah hath sent down to His Messenger but Allah is All-Knowing, All-Wise." (9-97)
Slavery is a real issue in the Arab world and the UN have not done anything to fight it. Several former slaves have become well known abolitionists.
Look at this man:
For you he is a black man from Africa. If you know more about him, you know that he is a Dinka from southern Sudan. For many Arab governments and many Arabs he is a slave, the property of another human being. In fact he is a former slave from Sudan.
(http://en.wikipedia.org/wiki/Francis_Bok)
In Mauritania about 20% of the population live as slaves, according to the South African Institute of International Affairs. The country suspended her diplomatic relations with Israel last month because of humanitarian concerns regarding the Gaza conflict. The president of Mauritania managed to say so with a straight face. And people applauded him for his stand for the rights of the oppressed.
And in the Sudan the black population (Nubians, Fur, Massalith, Dinka and other tribes) are at best non-citizens, usually seen as slaves, and at worst the victims of genocide. At the same time Israel is demonised for defending herself against a similar destiny. (I assume we can safely say that Israel and the Jews would not be the only non-Arab people under Arab control that would not be treated like non-citizens, slaves, or genocide fodder.)
Even in northern Iraq Sunni Arab tribal leaders still keep black slaves as personal servants (but not as labourers).
Former slave Simon Deng describes it best:
"While the life of a slave is like hell, there is no shame in being a slave; it is not a choice. There is only shame in being a master".
(http://www.iheu.org/node/1539)
Or look at this prison cell:
For you this is as a prison cell much too small for even the worst offender, a crime against humanity. For Saddam Hussein's government it was the correct place to store Kurds (plural) before they were executed.
The UN didn't care about this. And so-called anti-imperialists in the western world were still busy trying to find out if there is some remaining guilt the US or Britain could have for slavery and torture, two problems that can be savely ignored if done by Arabs to Africans or Kurds.
There are too many issues in the "Arab world", and the fact that it isn't really an "Arab" world is the least of them. However, the problems will not go away. Slavery is still a real issue, as is genocide and even civil rights. Kurds are people too, as weird as it might sound to someone who does not realise that it actually needs to be said.
I am not saying that Arabs shouldn't live all over the "Arab world". But I am saying that the peoples they rule ought to have a say in how their countries are run. Their native languages must be recognised and become official languages (and revived where necessary). And the governments of those mixed countries must be either monarchies (where the state is defined by the monarch and not by it being "Arab") or real democracies where all nationalities and religions are recognised. Israel grants the same civil rights to Jewish and Arab and other citizens, why can "Arab" countries not do the same with their Berber, African, Kurdish, and Assyrian populations?
Paraphrasing Simon Deng's statement I think it is fair to say that being an Arab in a country that also recognises non-Arabs as human beings and citizens is perhaps not a choice, but it is definitely no shame; whereas being an Arab in a country that enslaves or murders non-Arabs and not speaking up is a shame.