First: Given the current geo political situation two scenarios are very likely:
1) Iran-US renegotiation. This will ensure European and Chinese investment into Iran. Resumption of the IPI pipeline.
2) US tightening screws on Saudi. This will mean more Saudi investment in Chinese backed projects - like the recently announced restart of the 10 billion investment in Gwadar oil refinery.
A pipeline and rail line along the mekran coast makes biz sense since both Iran pipeline and Saudi refinery can benefit from it.
Second: There is a huge potential in the middle east market, fresh produce export, labour transport, etc. A 10-12 hour rail link between Karachi and Dubai will have enormous benefits - eventually it could even be extended to India.
Third: CPEC
One of things which does not come up during cpec discussions is a direct rail link between Africa and China. The Rail link connecting Hamburg Germany and Chengdu China only takes 14 days. It could be cut to 4 days if the railway tracks were of the same width.
The two routes are: China, central asia, Iran, Oman/UAE, Yemen and the Chinese base in djibouti, Africa.
China, Pakistan, Oman, Yemen and djibouti, Africa. The total travel time on rail would be around 4-5 days if international standard rail is used everywhere - as apposed to a month via sea.
The
straight of hormuz is only 40km long. And the
bab al-mandab is only 26km long. There is no need for tunnel or bridge as we have old technologies which can move trains over water: