The debris is unexploded munitions - ranging from bombs to artillery shells.
The second wave of maiming and death begins the moment civilians return to their homes in former battlefield areas.
Clean Up Your Mess
Now, more than 20 countries have ratified a new global treaty that binds warring parties to remove unexploded munitions from battlefields after their conflicts. The new pact went into effect on November 12, as nations attend a two-week summit in Geneva that is reviewing international agreements on rules governing the use of many conventional weapons.
The host of the conference - the International Committee of the Red Cross (ICRC) -- is also calling for a ban on the use of cluster bombs in all populated areas.
In Lebanon, 23 people have been killed and another 136 wounded by unexploded cluster bombs since fighting there ended in August.
In Laos, injuries continue some 30 years after the last major war ended. The ICRC estimates some 11,000 people have been killed or wounded by the millions of unexploded munitions still littering the country.
ICRC spokesman Peter Herby says statistics like this prompted the organization to launch an effort in 2000 to force warring parties to clean up after themselves.
"We were aware of the repeated problems of explosive remnants of war in places like Indochina following the wars there in the 1970's, also in Afghanistan in the Russian occupation period, and then what particularly focused our attention was that in the one year following the Kosovo conflict, which was a very short conflict, the ICRC had access to every part of that region and we documented all the casualties from explosive ordnance [there]," Herby says.
U.S., Russia Considering Ratification
Herby says that 26 mostly European countries have now ratified the clean-up accord -- enough to make it legally binding starting on November 12.
The countries that have ratified it commit themselves in future wars to clear the battlefields of any munitions they leave behind once the fighting ends.
The ICRC spokesman says none of the former Soviet Central Asian republics, except Tajikistan, has ratified the protocol. Nor have Russia, China, or the United States.
However, U.S. President George W. Bush has submitted the treaty to the Senate for ratification, and Russian President Vladimir Putin is expected to submit it to the Russian legislature soon.
Israel, which recently dropped cluster bombs in southern Lebanon -- leaving behind tens of thousands of deadly bomblets -- also has not ratified the accord.
Land Mines Not Included
Under the treaty -- known as the Protocol on Explosive Remnants of War -- states must clear unexploded ordnance themselves or pay for someone else to do it.
Former warring parties must also mark areas where unexploded munitions remain and warn civilians away from those areas until they are cleared.
And a former warring party is still responsible for helping clean up even if the other side wins and now controls the territory.
"Unexploded ordnance" as defined in this protocol does not include mines, which are covered in other international treaties.
Herby says that the new protocol will have no direct effect on today's post-conflict areas because it applies only to future wars.
Focusing Attention On A Crucial Issue
But he says it should raise attention to the problem of unexploded ordnance and this may encourage additional funding for existing ordnance-clearing efforts in many parts of the world.
"[The treaty] has created an expectation of what states should do when the munitions they use remain after a conflict," Herby says. "It will also create political forums in which the issue of explosive remnants of war will be regularly and consistently addressed. So, we hope that this will increase attention to the issue and also increase the resources available for clearance also of existing remnants of war left over from past conflicts."
The new pact went into effect as nations attend a two-week summit in Geneva to discuss protocols regarding the use of many types of conventional weapons.
The ICRC hopes at the conference to press states to also ban the use of cluster bombs, which scatter bomblets over wide areas. Many of the bomblets do not explode as intended, remaining behind as a lethal threat.
Because the bomblets happen to have interesting shapes and bright colors, curious children are particularly prone to pick them up afterward, losing limbs or lives as a result.
Eighteen countries so far have expressed support for banning cluster bombs, but the ban is opposed by Britain and the United States.
London and Washington argue that the alternative to cluster bombs is using an increased number of higher explosives in wartime, many of which may also not explode. They argue that any of those unexploded heavier munitions could take a higher post-conflict toll on civilians than do the bomblets.
The conference in Geneva began on November 7 and continues through November 17.
The states that have ratified the agreement to date are Albania, Bulgaria, Croatia, the Czech Republic, Denmark, El Salvador, Finland, France, Germany, the Holy See, India, Ireland, Liberia, Liechtenstein, Lithuania, Luxembourg, Malta, the Netherlands, Nicaragua, Norway, Sierra Leone, Slovakia, Sweden, Switzerland, Tajikistan, and Ukraine.