U.S. Invasion in Iraq, most estimates claim 15,000 - 30,000 Iraqi and 1,600 coalition deaths. The Lancet recently estimated 100,000 Iraqis have died as a result of the invasion.
Furthermore, there are several wars and dictatorships continuing from the 20th century. Mostly the number of deaths they caused during the 21st century is unknown.
See also [1] (http://users.erols.com/mwhite28/wars21c.htm).
This essay was originally written in 1991; hence the reference to 2091, a century later.
Almost all of these 2091 Earths look, at least on the outside, much the same way that our home looks a century before -- the land is divided into seemingly-arbitrary countries, and people are everywhere.
Perhaps in 2091 the Soviet Union (they may very well change their name back to Russia or some other name that we 20th century dwellers would not understand) will be outproducing every other country in economic, technological, and social markets...