The Royal Navy needs to expand its fleet of frigates in order to maintain security, according to the Royal United Services Institute.
A report published today by the defence and security think-tank argues that past underfunding and current extreme financial pressures will leave the fleet "dangerously weak" and inadequate for the task of safeguarding trade routes from pirates, terrorists or non-friendly governments.
"No one associates the full supermarket shelves, the availability of a range of other goods and the supply of fuels to power our homes, cars and industry with the free flow of sea trade," the report observes.
"The free flow that makes globalised trade and the creation of prosperity possible depends prominently upon the presence of naval units at sea, unseen and silent and therefore easily forgotten."
The reports authors, vice-admiral Sir Jeremy Blackham and professor Gwyn Prins, warn that unless the problem is addressed in the next ten years the navy will be left with only nineteen frigates.
And the paper argues the navy needs at least ten new cheaper frigates to help patrol major sea routes. ""Every trading nation is necessarily a maritime nation," the report says."And maritime presence demands numbers".
"Any trading nation has a critical interest in the secure use of the seas and the preservation of good order at sea... The dependence of the West, but especially of Britain, on use of the sea for its survival and prosperity is a geopolitical fact of life," write Blackham and Prins.
The report comes as the Ministry of Defence grapples with making the significant spending cuts demanded by the Treasury.
Speaking on BBC Radio 4's Today programme this morning, Prins said frigates were the "glue" that held the service together.
"They need to be there because they provide mass and they provide presence," he said.
"What we are lacking is the essential glue that makes the navy coherent".
But appearing alongside him, former navy officer Lewis Page said it was a mistake for the service to be "institutionally wedded" to buying more frigates.
"The lesson of Second World War was big service combatants, battleships, had been replaced by aircraft carriers," he said.
"Nowadays we have helicopters, and whenever a frigate does anything useful, which is quite rare, it is usually its helicopter that did it.
He added: "Just as we moved through the Second World War and got rid of battleships and had carriers, we need to get away from frigates in their current form."
But defending his report Prins insisted frigates were necessary to make sure "bad things don't happen". And he warned that if the government let the navy decline Britain would effectively be "signing off from serious international security".