Simi Jolaoso
BBC Africa correspondent

On the opposite side of the Bab al-Mandab Strait from Yemen lies tiny Djibouti, whose location has made it one of the most strategically important countries in Africa.

The narrow waterway between the African coast and Yemen connects the Gulf of Aden to the Red Sea and, beyond it, the Suez Canal, making it a crucial route for ships travelling between Europe and Asia.

That would explain the unusual concentration of military power along Djibouti's coastline.

The United States, China, France, Japan and Italy all operate military facilities there.

The US base at Camp Lemonnier supports around 4,000 US and allied personnel, while China opened its first overseas military support base in Djibouti in 2017. Both bases are only a few miles apart.

Japan's only overseas Self-Defense Force Base is also there; alongside long-established French forces and an Italian military base.

Their missions range from counter-piracy and counter-terrorism to protecting shipping, gathering intelligence and providing logistical support.

The location has taken on renewed importance as fighting intensifies just across the water.

Iran-backed Houthi forces are reported to have captured territory along Yemen's Red Sea coast, including the strategic island of Perim in the Bab al-Mandab Strait.

Several of the world's biggest military powers already have forces positioned beside this crucial shipping route.

So while much of the attention is currently on Yemen, the African shore illustrates just how much is at stake.