From the very inception of the War on Terror, this administration has attempted, both rhetorically and strategically, to present Al-Qa'eda as a unified terrorist organization with a handful of supposed puppet-masters. Unfortunately, this assessment is tragically false. Global terrorist networks are fundamentally different in both structure and strategy than any previous threat to international state security. Unlike traditional warfare where power emerges from a single locus, Al-Qa'eda is a radically individualized movement full of mini-leaders, self-starting cells, and zealous lone gunmen. The killing of any localized "leader" does nothing whatsoever to affect the actual power base any more than the ousting of Hussein did to staunch the threat posed by Iraq.
Despite rhetorical proclamations to the contrary, this administration has remained entrenched from the beginning in a pre-9-11 mindset. This tragic inability to think outside the box is perhaps the single most significant reason why Bush is losing a war of his own creation. The bottom line is that we are not dealing with a foreign government, nor are we tackling a guerilla movement centered around a charismatic individual. Were this to be the case, it would certainly be a reasonable strategy to target the enemy's power locus (their government or leadership) as the entity responsible for directing the country's assets against you.
However, what this administration seems to have a difficult time grasping is that terrorism functions as an essentially populist movement where power derives from the bottom, not the top. There is no single government or leadership that will cause the beast to come crashing down but rather hundreds or maybe thousands of tiny, quasi-governments capable of acting with complete autonomy. Within such a network, Zarqawi no more represents the power behind Al-Qa'eda than any other zealous individual motivated to strike against U.S. interests.
Were this administration to finally get serious about fighting this war, rather than playing the role of cowboy in a 'dead or alive' posse, they would confront the ideology to which terrorists claim allegiance rather than the individual, armed expression of that ideology. In this way, perhaps the administration could cease inserting itself as a causal factor into the very problem is claims to be solving.
The Hindsight Factor