Water.

This is coolbert:

As it has been in the past, as it is now, but will not be in the near future?

Thanks here to Strategy Page for this item:

"Logistics: Water Purification Made Simple And Cheap"

In the historical sense the two biggest killers in warfare have been feet and water.

1. Having bad feet, unable to keep with the march and becoming separated from your unit, the straggler set upon by local civilians, marauders or partisans and killed.

2. Water! NOT having enough water to drink or drinking bad water.

"For the military clean water is a necessity, otherwise the troops will suffer more than the locals (who have developed some resistance to the bad water). The foreigners often have digestive systems with little experience with bad water and are thus more vulnerable."

AND A CHEAP AND EASY SOLUTION TO THIS AGE-OLD PROBLEM HAS BEEN FOUND? Read the entire Strategy Page article and decide for yourself.

Water purification thanks to the advances of modern science now available to everyone and at a cheap price! Thanks to the research with a military application in mind BUT ALSO useful to the civilian populace as well!

Who could ask for more?

coolbert.