Throughout the intense three decades from the first Arab-Israeli war in 1948 to the 6 October 1973 (or Yom Kippur) war, several Middle Eastern players had tried to close the Bab al-Mandab strait to other regional actors. Today the Houthis militia in Yemen is building leverage in the region by trying to control passage through Bab al-Mandab. Although countries across the Middle East - and many beyond it - are paying the price, different stakeholders see the situation in the Red Sea differently.

Most Western countries see the Red Sea from an economic perspective. For them, freedom of navigation underlies energy and trading routes. For most countries in East Africa, the Red Sea is essentially a matter of access to and control of waters, or their denial of these power generators. For Saudi Arabia, Bab al-Mandab and the Red Sea make a lifeline. For Egypt, however, the Red Sea is a frontier.

Mohammad Ali Pasha, arguably the founder of modern Egypt, along with his son and the commander of his armies, Ibrahim Pasha, and Ibrahim’s son, Ismail Pasha, all recognised, throughout the nineteenth century, that Egyptian security extended southwards, deep into Africa, as much as northwards to the Levant’s approaches to Anatolia. And although their ambitions in East Africa yielded vastly different outcomes, the understanding that Egyptian security extends far beyond the country’s borders has remained one of the few points of consensus among all the serious strategy disciplines that have studied Egypt’s history and geography.

The Suez Canal has underscored this understanding. For the world, the Canal transformed the Red sea from an important trading route into the old world‘s most strategic maritime highway. For Egypt, the Canal has made the Red Sea an integral element of the country’s national security. This is why whereas the idea that Egypt controls the sea’s northern gate (at the Canal) is correct, perhaps the more accurate understanding is that, for the 150 years since the inauguration of the Canal, the Red Sea has been one of Egypt’s most important exposures.

Exposures can be economic. The Houthis’ threat to navigation through Bab al-Mandab has already cost Egypt, in the past few years, around 50 percent of its annual USD9 billion of Canal revenues.

The strategic cost, however, is more significant. The notion that the Red Sea is an exposure means it is effectively a border that Egypt lives along. In this understanding, the Red Sea is not merely a corridor that, at minimum, must have freedom of navigation to ensure low costs and premiums, and at maximum, is to be protected through coalitions of the navies of different countries. Seeing the Red Sea as an exposure imposes on Egypt a difficult question : not only who can harm the Egyptian economy, but who can attempt to redraw the contours of that frontier?

The Nile lends these questions acute importance. Seen from Cairo, the Red Sea and the Nile are one strategic theatre. Whoever establishes serious presence on the Red Sea shores can potentially threaten the routes of the Nile waters.

Recent Egyptian investments make the Red Sea dossier more pressing. The potential of the Suez Canal region to grow into a logistics hub serving the Eastern Mediterranean and trading routes to Sub Saharan Africa - along with key energy pipelines (such as SUMED) - are among Egypt’s most important geoeconomic offerings in the foreseeable future. The realisation of this potential depends upon the Red Sea returning to be a safe transit route for energy and trade.

There are soft elements at play here as well. The sea’s far shores are those of al-Hijaz and Yemen. For many Egyptians, the first holds a sacred place in their psyche; the second is where thousands of Egyptian soldiers bled in the 1960s. The emotion attached to the first and the memory of the second push the Egyptian consciousness in opposing directions. Both, however, exact tolls and evoke feelings. Anyone who ignores the calls of memory on Egyptian thinking and behaviour does not understand the country and its society.

The developments in the Red Sea in the last few years are a reminder that whenever there is an assertion of power to control who passes through Bab al-Mandab, there is a cost, strategic and economic, to Egypt. This is why while the world is asking whether ships can pass through the Red Sea, Egypt’s calculus must be based on who holds that frontier.