The task facing Britain’s defence industry has never been so clear: “It’s now about how to keep our soldiers from coming back in body bags.”

This opinion, voiced from within the industry, is widely shared as the conflicts in Iraq and Afghanistan shape the global defence trade and companies seek to respond to changing military threats.

It will be repeated when the industry’s trade fair begins in London today.

The main theme of the Defence Systems and Equipment International (DSEi) exhibition is “force protection”.

The event will be dominated by equipment designed to keep soldiers alive, not by its traditional focus — offensive weaponry.

Body armour, gas masks and armoured vehicles will all feature prominently and the organisers have arranged a force protection demonstration area to show off the equipment’s effectiveness under fire.

Demand from military commanders for defensive equipment has grown massively since the invasion of Iraq morphed into combating a guerrilla warfare waged by insurgents.

Western armed forces had been moving towards a doctrine of light and fast strikes, characterised by their attack on Iraq, but British and American troops have come under sustained assault from mortar bombs and roadside mines and missiles during their operations and much of their existing equipment has been shown to be inadequate.

Moreover, methods that have proved so successful for Iraq’s terrorists are being aped by the Taleban in Afghanistan.

Military vehicles, such as the American Humvee and the British Land Rover, are insufficiently armoured to protect troops against snipers and improvised roadside bombs.

This has led to armour plates being attached to vehicles as temporary protection, but longer-term solutions are being sought by both the British and American military.

Thousands of Mine Resistant Ambush Protected (MRAP) vehicles will be ordered by Britain and the United States over the next few years and nearly every big defence company will be demonstrating its solution during the exhibition.

The American MRAP requirement is budgeted at $7 billion (£3.5 billion). Britain’s equivalent, FRES, or Future Rapid Effects System, could cost up to £13 billion.

BAE Systems, Europe’s largest defence company, has been one of the biggest beneficiaries of this urgent need to upgrade vehicle armour.

BAE will be able to claim this week that it has become the world’s largest manufacturer of armoured vehicles, after a buying spree in recent years in which it has acquired some of the industry’s most famous names.

Representatives from Armor Holdings, which BAE bought for $4.5 billion this year, will be at DSEi under the umbrella of their British parent for the first time.

Armor makes protection plates for Humvees and is selling an MRAP transport vehicle. BAE and Armor have won about $1 billion of MRAP business so far and they hope to take a larger portion of this market having merged their product offerings.

Unmanned military equipment will be another area of interest for commanders hoping to reduce threats to their troops.

BAE, Thales and Lockheed Martin will be discussing their unmanned aerial vehicle programmes, which are used for reconnaissance and, occasionally, offensive missions.

BAE will also be showing a concept called the UXV Combatant, or Mothership, at DSEi.

This warship is designed to operate as a base for a fleet of unmanned vehicles, including aircraft, helicopters, surface ships and submarines — an extreme example of how companies are responding to military pressure to improve force protection.

Marketplace

— The Defence Systems and Equipment International exhibition was first held in 1999 in Chertsey, Surrey.

It combined the British Army Equipment Exhibition and the Royal Navy Equipment Exhibition, which were held on alternate years between 1976 and 1991 before being combined in 1993 and then privatised

— About 25,000 visitors attended the last exhibition, in 2005

— There are new country pavilions from Bulgaria, Lithuania and Turkey, as well as expanded pavilions from France, Spain, Italy, Denmark, Finland, Germany, the Netherlands and Norway

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