"Large" is a pretty non-specific number to cause you to go off on an arithmetic spree to try prove it false. Of course it's not large compared to WWI or WWII -- and I'll note that the huge number of children who grew up in mother-only homes in those eras did just fine on the whole. Compared to the generation in which the people who are currently having babies grew up, there will be signficantly more children growing up over the next 15-20 years in war-widow-headed homes.
Again, Shrinks, the number of war dead from Iraq/Afghanishtan is 0.000000013% of the total male population in the US. And that assumes all war dead are fathers. And if "going off on an arithmetic spree" by citing simple statistics to expose your analysis is troubling, well, welcome to FR. Facts count.