Hull writes a flawed, but interesting, study about the relationship between the ideological underpinnings of the Imperial Germany Army and Germany's military failures since the Franco-Prussian War. Hull main point is that the Prussian (and then Imperial German Army's, Gr. Reichswehr's) overwhelming bias toward operational effectiveness both created, and was created by, a view of warfare so dedicated to the dstruction of enemy forces that it was blind to the political and strategic dimensions of war. As a result, Hull claims, German logistics were problematical, German Military Occupation was disastrous, German strategy was neglected, and German policy was virtually non-existent. Put more broadly, she believes that the German Army was so focused on winning battles and campaigns that it did not have the foggiest idea of how to win (or emerge favorably from) a larger war.
Hull also aims at some bigger points, which she only touches on indirectly. First, her analysis would imply that Germany's conduct of World War II was largely a continuation and (great) amplification of its conduct in World War I and in Africa. Many prominent Nazis -- Hitler, Roehm, and many others come to mind -- were front line soldiers in World War I and had absorbed that military culture. Second, and related, the Imperial German State in general had so completely absorbed and deified that military culture that the German government shared the same failings as the German military.
There is much in what Hull says. But there are also several significant faults in her analysis. First, she dislikes the German Army, despite attempts to remain objective, and thus sometimes makes it look less effective than it was. For example, she claims that German and French losses at Verdun were about equal, something few others would support. Second, she is sometimes ambivalent, if not contradictory. For example, she condemns the German High Command for failing to acknowledge when it was beaten, as for example when the United States entered the war. Yet she condemns its 1918 offensive strategy as reckless gambling, claiming that Germany could have held out far longer if it had adopted a more defensive strategy. Now Hull is probably right -- once the United States entered the war, Germany was probably doomed. But if this is true, Ludendorff and Hindenburg would seem to have done Germany a favor by ending the agony in one year rather than three or four through their adoption of an all-or-nothing strategy.
Actually, Germany came fairly close to a favorable result in World War I, even if it could not have "won" outright. If it had continued to negotiate in good faith, eschued unrestricted submarine warfare, and maintained a relatively defensive posture in the West, Russia would have collapsed and there would have been a real chance at an acceptable peace. Of course, as Hull's own analysis suggests (it would have been helpful if she had been more explicit here, but her fixation on Germany's weaknesses prevents her from doing so), Germany was incapable of formulating such a policy. She was commited to absolute victory and her civilian government was too fragmented and too military-minded to carry out a flexible political strategy. For this inflexibility, Hull rightly claims, Germany military culture was greatly to blame.