The recent incident with the container ship stuck in the Suez Canal serves as a reminder: this canal is not the only sea route we should be worried about using.

What else? What would the other 'objects of concern' be?

The Suez Canal is a highly significant shipping route, but it is not the only one. There are three other straits and a canal on Earth that facilitate international (internationally significant) ship and cargo transport. The Strait of Malacca, which connects the Indian and Pacific Oceans; the Bosphorus Strait between the Aegean and Black Seas; the Strait of Hormuz at the entrance to the Persian Gulf; and we must not forget the Bab-el-Mandeb Strait near the Arabian Peninsula. And, of course, the Panama Canal.

The Strait of Malacca is made dangerous by pirates, but... the greater danger is posed by the dense ship traffic. Large cargo ships at maximum speed (much like on a two-lane road) close to each other, with minimal maritime traffic control... That would be a brief and clear description of the Strait of Malacca. 'When on duty, this was the most unpleasant sea route to navigate; a ship's captain would usually stay awake until the strait was behind them...'