There should be some purpose to build the sethu, which we (ordinary people) cannot analyse. What was the strategic planning analyse / implement by Lord Rama we cannot even imagine.
Infact for your information Rawan was using aeroplance (puspak viman), so the techonology of flying was there than why not ships. But to make the bridge was surely a higher purpose or goal.
The purpose to unite Srilanka with India.
And for all general public to use this sethu for business and religious purposes.
