Part 1

This is a very large question. What was trade like? Covers a massive concoction of different topics. But from your previous statement on the US navy im going to presume you are mostly interested in the naval aspects of trade protection rather than civilian and economic. I think even this is too large a question to really tackle but I will have a go.

I would suggest that this period is best trying to tackle through some aspects of the huge history of the legality of states using mechanisms to stop private trade, and the ramification this has for wider naval theory. The second part is obviously too massive to really deal with, but the first I think could be simplified by viewing it through a lens of increasing complexity and interconnections of global trade, and the growing economic and maritime strength of Britain.

While 19th century Pax Britannica as a term conjuring images on near omnipotence is as misleading as a 20th century Pax Americana, I think for this question it serves its purpose. From arguably the end of the Napoleonic wars until the First World War, and debatably between the First and Second World War, global maritime trade was controlled by the double sided themes of British naval power and increasing international maritime law

Crudely I would describe the period prior to 1750 as the period of indiscriminate commerce warfare and privateering, one favouring the aggressive underdog such as the Dutch and Britain conducting campaigns where goods and wealth are directly taken from adversaries. From 1750-1850ish you can see the development of mechanisms of truly effective commerce war, the ability to blockade whilst conducting widespread defence/raiding of trade. But within an increasingly complicated global economic system the acts of trade warfare are potentially negative to all belligerents and neutrals. From the early 19th century until the end of the second world war you have attempts to create international laws based against a background of British maritime power.

In some ways, overly simplistically, the regulation of international maritime law can be seen in the light of nations grasping and groping their way from mercantilist notions of monopoly of wealth towards more interdependent trade during the latter part of the 18th century. The previous approaches to naval warfare of widespread state sponsored privateering and concepts of “self funding” wars had already been thoroughly challenged. The complexity of the international trade system, especially finance and insurance, had already shown that indiscriminate trade warfare was often counter productive. As far back as the Spanish War and Austrian Succession in the middle of the 18th century, Britain had already experienced the difficulties commerce warfare led to if significant parts of foreign trade was financed and insured by your own nationals, and parts of your economy relied on some aspect of foreign provided trade. For example during the early stages of the War of Jenkins Ear in 1739/40 attempts to interdict Spanish treasure fleets, similar to attempts for the past 200 years were now complicated by the fact that the Flota were part owned by neutral French merchants and the goods were insured by English insurers! and British exporters to France would find French merchants light on funds because of their disrupted Spanish trade. While the Napoleonic wars might have seen a last hurrah for attempts to monopolise trade into continental Vs British global systems, the impact on neutrals and the international system in general was a problem, with ramifications such as war with US.

The position of neutral vs belligerent rights was essential to the problem, and remained so probably until the second world war and the United Nations. The British appraisal of the requirements for cooperation in order to trade effectively and profitability was in some ways distorted by British power, both maritime and economic. The British position at the centre of trade and finance, was on one hand that they could use brute force (economic and naval) to exert their will, while on the other recognising that they perhaps had most to lose from disrupting the system. Broadly speaking Britain wished to provide themselves with the greatest flexibility possible to do as they wished and to retain the right to confiscate all trade of enemies during times of war, even in neutral carriers. This is in contrast to the positions of France and the US which viewed that the primacy of “free goods, free ships” in neutral shipping. Both these legal definitions are entirely entwined with their respective maritime power, neutral rights promoted by weaker maritime nations in response to British ability to exert their view with might. In many ways this view remained unchanged until the second world war. However, Britain increasingly begins to see the use of maritime law as a useful way of safeguarding their own position and wealth, and potentially as mechanism of controlling threats and their own defence expenditure.

In part this was prompted by the various changes to the global strategic situation such as the war with Russia in the 1850s. Russia was distinctly invulnerable to British commerce warfare and potentially in a position to issue widespread letters of marque against British Shipping. The growing/shrinking position of France over the period as distinct underdog changed the dynamic also. Now it was France that now had the most to gain from indiscriminate trade war and Britain most to lose. Britians Empire was wide and hard to defend global shipping without enormous naval expenditure. In the aftermath of the war with Russia, the Declaration of Paris in 1856 effectively made privateering illegal, neutral cargo were respected as long as they were not “contraband”.

However this did not solve problems for Britain as Russia and France began a more concerted approach to create modern commerce raiders specifically to threaten global British trade, forcing Britain to expend effort and money on trade defence, diverting resources away from approaches that could be used aggressively against their own coasts and trade.

Britain was the centre of global trade. Financially London was brokerage hub of the world, global trade was lubricated by loans and insurance from London. Britain was the worlds largest physical importer and exporter and trade was essential to British prosperity, yet Global trade in its entirety is just as important, providing the mechanism for a substantial part of British invisible exports. Imperial trade routes span the globe, but just as important are the routes to the Americas. In 1896, after a period of distinct German maritime challenge, British owned shipping still accounted for 56% of all global shipping and this does not include shipping owned by colonies and dominions. I don’t have figures for earlier, but I expect its greater still.

This is all to clumsily say that British naval power was distinctly ordered and directed to maintain and promote this domination. The dual importance of trade protection and attack is essential to planning and theory throughout the joint threat of Russia&France, through to the challenge of Germany, and the threat of US and Japanese strength post first world war. Embargo, blockade and ocean sea lane interdiction/protection are central to war plans with all potential adversaries. In “peacetime” naval forces are used to promote trade and empire throughout the globe through classic gunboat diplomacy, slaving suppression, naval theatre, and anti piracy. Direct trade protection in peacetime was a continuous feature of the Royal Navy, naval forces in China throughout the early 20th century is a great example.

Alongside this naval power there were complicated attempts to legally codify the rules of maritime warfare. These were driven by the difficult dilemmas of how best to protect British trade, through agreements, that while protect trade impinge upon freedom of action, or through trusting in British seapower to protect through force? To seize or not seize? The debates, internally and internationally around the legality of blockades and seizure is far too long to describe. Suffice to say, that despite widespread international concern and despite their own reliance on imports, Britain generally fell on the side of maintaining their freedom of action during war. This was best expressed during the First world war, but continued to be exercised during the interwar period. This is generally termed short hand Belligerent Rights.