Should the term Allah used exclusively by Muslims?

A recent decision by the supreme court in far away Malaysia has relevance to our discourse in the US. The court ruled to allow Christians to use the word Allah in their worship. The reason for the court challenge was the fear that some Christians were using the word Allah in a surreptitious attempt to proselytize Muslims. The Christians disagreed saying the word simply means God in Arabic and the high court in Malaysia agreed. It is worth remembering Malaysia is an overwhelmingly Muslim majority country (approximately 60% Muslim and about 9-10% Christian) that practices a pluralistic, inclusive version of Islam.
The Malaysian court’s decision is bolstered by the fact that Arabic language Bible uses the word Allah for God. Adjectives like insha-Allah (God willing) masha-Allah (an appreciative appellation of God’s will), subhan-Allah (God be praised) are commonly used by both Muslim and non-Muslim Arabs. Outside the Arab world the term Allah and its derivatives are used only by Muslims that may have been part of the reason for the court challenge.
There are references in the Qur’an that clearly allude to the fact that Allah is a pre-Islamic term. Referring to the self serving use of God by pre-Islamic Arabs the Qur’an states, “---- then comes a stormy wind and the waves come to them from all sides, and they think they are being overwhelmed: they cry unto Allah, sincerely offering (their) duty unto Him, saying "If Thou dost deliver us from this, we shall truly show our gratitude!" (10:22)” In fact early on Allah did not appear to be the Qur’an’s favored term for God. “Rahman”, meaning the “Compassionate”, was used so often that observers felt it would be the chosen term.
Scholars have speculated that the word Allah may be the combination of “al” and “Ilah’ or “the God.” The confessional statement Muslims use in declaring their faith “La Ilaha Illal-Lah” is most frequently translated as “there is no God but Allah” or “there is no God but God.” The difficulty with the first translation is that it implies, unintentionally, that there is an exclusive God for Muslims. Nothing could be farther from the concept of God in Islam. God, Muslims are taught, is universal. He is God of all humanity, the Creator and Nourisher of the universe. The rationale for a universal God formulation is to achieve unity of mankind through a unified God, but not necessarily the same faith. The second formulation “There is no God but God” though powerful in Arabic, sounds inane as most literal translations are. Some argue that intellectually God may be defined only in negative terms, as whose attributes are beyond mind's eye and whose non existence is inconceivable; therefore the “no God but God” makes sense. A better translation would be the simple statement “God is One.”
Nevertheless the Arabic word Allah is well suited to the stringently monotheistic concept of God in Islam. The word has no plural to it, nor does it have a gender. In Islam one can never ask the question “is God female?”
Muslims talk about the ninety nine names of Allah (Asma-ul-hasana) that is meant to represent the numerous attributes of perfection. Scholars have wondered if there is a hundredth hidden name that holds the mystery of existence.
Much misunderstanding remains in the use of the word Allah and how to accurately translate it, but the Malaysian high court’s decision has cleared the air a bit and struck a blow for common sense.