Turkish investments and political engagement across the Middle East have been steadily rising for many years as part of Ankara's effort to gradually reassert itself in its historic Ottoman sphere of influence. As the two major powers in the region, the Ottoman and Persian empires historically fought land wars focused on Mesopotamia and neighboring states. The waters stretching from the Persian Gulf through the Arabian Sea were in the Persian sphere of influence, and the Ottomans had no direct access. However, through Mamluk Egypt and control over Aden in Yemen, the Ottomans had a land route to the Gulf of Aden, and by extension the Red Sea, before the construction of the Suez Canal. Turkey's regional rise now requires Ankara to push its influence beyond its borders, bringing it to encroach on the boundaries of Iranian influence. Turkey is building ties with the Kurds in northern Iraq (and experiencing Iranian pushback) and supporting Syria's rebels. Turkey can expand into Iran's naval sphere through the Suez Canal to positions in the Gulf of Aden; from there it could move up the coast of Oman into the Arabian Sea and even the Persian Gulf. In those maritime regions, Turkey's efforts to inhibit Iranian influence have been aided by the massive U.S. naval presence, which severely constrains Iranian power projection. Somalia and Yemen, both troubled Sunni Muslim states currently undergoing political transitions, possess valuable ports in Berbera and Aden, respectively, which present an opportunity for Turkey to further its own presence and to check the Iranian presence in the southern waters off the Arabian Peninsula.