Defense Secretary Robert M. Gates has proposed a major overhaul of the way the Pentagon and State Department do nation-building, seeking to end friction between the bureaucracies by putting them jointly in charge of three huge new funds aimed at stabilizing strife-ridden countries. The proposal is aimed at addressing problems that have dogged the U.S. effort in Iraq and Afghanistan -- particularly, disputes over whether civilians or the better-funded military should be in charge of stabilization. But Gates's proposal goes beyond those conflicts to address what the military increasingly sees as the greatest threat to the United States -- failing...