Well, according to my knowledge, it is oil.
Because the "Arabian Peninsula" is dominantly and mainly occupied by "Arabians" for a couple of millennium's now.
because of the trading situations in the countries and communicating with the other countries will just ended with violences and wars
it is important because it is their most valuable resources. without it they would be poor.
Refugees and Civil Wars have made it difficult to build healthy economies in the Eastern Mediterranean countries because refugees cannot find work to support themselves and find homes, food, etc. Civil wars are also a problem for the economy of the Eastern Mediterranean countries because they are depleting valuable resources that could be sold as profit such as oil, the principal resource in the Arabian Peninsula.
Because it is surrounded by water
The countries' Immigration policies are the most lenient in the Middle East.The countries of the Arabian peninsula rely heavily on foreign workers to grow their economy.The countries of the Arabain peninsula rely heavily on foreign workers because they themselves are not able to do the works available in their country.
The Arabian Peninsula is sparsely populated primarily because most of the land mass is a parched desert, unable to support life.
Mecca was an important city for Arabs on the Arabian peninsula, before Islam because it was a worship place for them.
People cannot be farmers in the Arabian Penninsula because it is a desert. In deserts it is hard to farm because it doesn't have much water.
Oman is not part of Saudi Arabia because Oman and Saudi Arabia is a different countries.
it is important because it is their most valuable resources. without it they would be poor.
because oases are good places for crops, which is good for trade.