Absolutely. GW was a great guy, and should be rated highly. But AL held the union together--at times by almost his sheer will alone. His constant efforts to win the war--and his plan for winning the peace--have had much more of an influence on how the country has operated since.
Right or wrong--whether you agree with his positions or not--its true that without him at the helm, we would be two (or more) nations.
Are we not in the process of becoming "two (or more) nations" _again_, right now? One needs to do no more than look around....
- John