Exactly as it reads. If you are not a Muslim, you cannot serve in the military of a Muslim nation. Seems they are more aware and conscientious about making sure their military personnel have the same goal in mind for maintaining Islam as their country's religion. Allowing non-Muslims into their military would compromise their own national security. Something that our own military leaders are beginning to find out regarding actions by Muslim soldiers within the ranks of U.S. armed forces.
Here are just a few excerpts and examples, from the Constitutions of the following Islamic countries ensuring that Islam is the priority:
From the Saudi Arabia Constitution:
Chapter 5 Rights and Duties
Article 23 [Islam]
The state protects Islam; it implements its Shari'ah; it orders people to do right and shun evil; it fulfills the duty regarding God's call.
Article 33 [Armed Forces]
The state establishes and equips the Armed Forces for the defence of the Islamic religion, the Two Holy Places, society, and the citizen.
Article 34 [Military Service]
The defence of the Islamic religion, society, and country is a duty for each citizen. The regime establishes the provisions of military service.
and;
From Iran's Constitution:
An Ideological Army (Preamble Excerpt of Iran)
In the formation and equipping of the country's defence forces, due attention must be paid to faith and ideology as the basic criteria. Accordingly, the Army of the Islamic Republic of Iran and the Islamic Revolutionary Guards Corps are to be organized in conformity with this goal, and they will be responsible not only for guarding and preserving the frontiers of the country, but also for fulfilling the ideological mission of jihad in God's way; that is, extending the sovereignty of God's law throughout the world (this is in accordance with the Koranic verse "Prepare against them whatever force you are able to muster, and strings of horses, striking fear into the enemy of God and your enemy, and others besides them" [8:60]).
Article 144 [Islamic Army]
The Army of the Islamic Republic of Iran must be an Islamic Army, i.e., committed to Islamic ideology and the people, and must recruit into its service individuals who have faith in the objectives of the Islamic Revolution and are devoted to the cause of realizing its goals.and;
From Iraq's Constitution (Adopted 1990)
Article 4 [State Religion]
Islam is the religion of the State.
Article 28 [Educational Goals]
Education has the objective of raising and developing the general educational level, promoting scientific thinking, animating the research spirit, responding to exigencies of economic and social evolution and development programs, creating a national, liberal and progressive generation, strong physically and morally, proud of his people, his homeland and heritage, aware of all his national rights, and who struggles against the capitalistic ideology, exploitation, reaction, zionism, and imperialism for the purpose of realizing the Arab unity, liberty, and socialism.
and;
from Syria's Constitution:
Article 3 [Islam]
(1) The religion of the President of the Republic has to be Islam.
(2) Islamic jurisprudence is a main source of legislation.
and;
from Yemen's Constitution:
Article (1)
The Republic of Yemen is an Arab, Islamic and independent sovereign state whose integrity is inviolable, and no part of which may be ceded. The people of Yemen are part of theArab and Islamic nation.
Article (2)
Islam is the religion of the state, and Arabic is its official language.
Article (3)
Islamic Shari'ah is the source of all legislation.
and;
from Pakistan's Constitution:
So that the people of Pakistan may prosper and attain their rightful and honoured place amongst the nations of the World and make their full contribution towards international peace and progress and happiness of humanity :
Now, therefore, we, the people of Pakistan,
Cognisant of our responsibility before Almighty Allah and men;
Congnisant of the sacrifices made by the people in the cause of Pakistan;
Faithful to the declaration made by the Founder of Pakistan, Quaid-i-Azam Mohammad Ali Jinnah, that Pakistan would be a democratic State based on Islamic principles of social justice;