Gen Sir Richard Dannatt said soldiers were sometimes greeted with indifference on returning from service.
He contrasted the attitude in Britain with support for soldiers among people in the United States.
A "willingness to serve in such an atmosphere again" could be sapped, he said in a speech in London.
Gen Dannatt told the International Institute for Strategic Studies: "Soldiers want to be understood and they want to be respected for their commitment.
"When a young soldier has been fighting in Basra or Helmand, he wants to know that the people in their local pub know and understand what he has been doing and why."
"Soldiers are genuinely concerned when they come back from Iraq to hear the population that sent them being occasionally dismissive or indifferent about their achievements," he added.
Gen Dannatt compared the situations in the UK and the US, where firms offer discounts to serving soldiers and people shake the hand of those in uniform.
He said that, in the UK, "we still have a nation that, at times, seems immune to homeless and psychologically-damaged soldiers".
"As operational commitments have become more intense, so has the need for support from the nation," he said.
"We must move from being a society that uses the military as a political and media football and more towards seeing the military for what it is."
That was "the instrument of foreign policy conducted by a democratically-elected government acting in the name of the people".
Campaign support
Gen Dannatt also called for a radical rethink on the equipment used in the British Army.
He said that "too often we have been seduced by high technology".
He called for more money to be spent on "getting the very lowest level right".
This involved "equipping the man first and building the system around him", Gen Dannatt added.
Major General Patrick Cordingley, who commanded the Desert Rats during the 1991 Gulf War, agreed there was a lack of understanding about the role of armed forces in Iraq and Afghanistan.
"I think the real problem is that the armed forces are at war and the country isn't, therefore there is an inevitable misunderstanding of what our armed forces are doing," he told BBC News 24.
There was a great difference between the public's attitude to the first Gulf War and the second, he said.
"The first Gulf War was seen to be just, was seen to be the correct thing to do and the country was right behind everybody who went down and what went on.
"The second Gulf War was a very different situation indeed - probably not just, perhaps not even legal and a 50-50 split in the country - not a popular war."
He added that he believed the media and the Ministry of Defence were partly to blame for not explaining what members of the armed forces were doing in Iraq and Afghanistan.
