With the rise of computers and war gaming, the strategies employed by the US military in its latest campaigns are as good as any ever employed in history. Gulf War I, Afghanistan and Iraq are instant classics, and Fallujah is just the latest example. These don't get credited to a single individual, so we don't have our Alexander, but our strategy is just as good.
I think that Sherman's pillaging of the South was contemptuous and dishonorable. That's not something you do to your own people, even if they were rebels.
Guderian was a great general, I agree. In my opinion, he was on par with Rommel - if not, above him. Funny that he is now widely overlooked in military history.