Blockade

A definition of blockade leads into the Royal Navy's First World War effort to preserve British trade while denying Germany the imports that sustained its industry and food supply.

The video separates blockade from siege by contrasting control of movement and trade with the direct violence used to weaken and capture a defended place.

The Anaconda Plan exploited a Confederacy whose river network led toward blockaded coasts, whose east-west rail connections were weak, and whose industry could not readily replace imported machinery, while Union industry and external supply routes sustained the northern war effort.

The Anaconda Plan illustrates why a blockade can be strategically decisive even when many blockade runners still get through: each lost export also reduces the enemy's ability to finance later imports.

A close blockade puts small vessels near the enemy port to watch for a sortie, while the stronger fleet waits farther offshore where weather and coastal hazards are less dangerous.

How closely ships hold a port depends on geography, fleet size, and whether commanders want concealment, warning time, or conspicuous psychological pressure.

Trafalgar did not end the war, but its destruction of ships and experienced French naval personnel made a rapid fleet recovery - and therefore an enforceable blockade of Britain - impractical.

Napoleon's Continental System tried to prohibit European trade with Britain, but France lacked the sea control needed to stop British ships and smugglers from reaching the continent.

Attempts to enforce the Continental System helped drive conflict in Iberia, Russia, and Anglo-American trade while Britain diversified its commerce beyond Napoleon's reach.

A loose blockade keeps warships out of hazardous coastal waters; the video then argues that unrestricted submarine warfare resembles siege warfare more than a conventional blockade.

Blockade enforcement creates immediate disputes over neutral shipping, from whether neutrals may trade with both belligerents to whether a submarine can identify a ship before attacking it.

Even when neutral ships are not attacked, boarding them to search for contraband, seize or buy cargo, and identify sailors can turn enforcement into a major diplomatic dispute.

Pacific blockades apply naval pressure during nominal peacetime, using control of sea access to compel a political decision without beginning a general declared war.

Embargoes and economic, diplomatic, military, sporting, environmental, or individual sanctions promise narrower pressure than blockade, but only when states coordinate and intelligence can identify prohibited movement.

A modern information blockade could isolate a country from the internet, while the routes of undersea cables reveal how digital communications still follow much of the geography of maritime trade.

Economies that import raw materials and depend on exporting manufactured goods are especially vulnerable because even a partial blockade can interrupt both production and revenue.

The First World War British system controlled trade routes from a distance, whereas German attacks in the world wars tried to destroy shipping without establishing comparable control over the routes themselves.

The closing argument asks whether a navy can sustain the cordon and whether operations on land can close the continental routes that maritime power cannot reach.