What is the critical argument of Bob Woodward's Plan of Attack, and how could one argue that?

Bob Woodward, award winning journalist who along with Carl
Bernstein exposed the Nixon administration criminal activities cover up called
Watergate, poses the question in Plan of
Attack of whether the United States could justify a unilateral (single
instigator) war against Iraq and Saddam Hussein that violated the sovereignty of an
independent nation. To find the answer to his question Woodward investigated the
dynamics of the George W. Bush administration by examining records and tracking the
behavior and statements of the administration's key
personalities.

For instance, Woodward
examined General Colin Powell's actions and statements,
particularly in relation to Powell's disagreement with the decisions being made about
the war and his attempt to dissuade Vice President Cheney from advocating the unilateral
Iraq/Hussein war. He also investigated the link between Scowcroft and the elder Bush,
since it appeared that Scowcroft's messages about the inadvisability of such a war were
covert messages opposing said war that originated from the elder Bush and were intended
for George W. Bush.

Woorward's intention was to provide an
accurate and detailed account of why George W. Bush led the U.S. into an unprecedented
preemptive war against Iraq with the aim of deposing its dictator, Saddam Hussein,
notwithstanding that Iraq is a sovereign nation, such as the U.N. Charter upholds as
inviolate. Woodward's conclusion and critical argument is
that even though George W. Bush could not justify a war against Iraq according to the
U.S. Congress and the U.N. Charter definition of a justifiable war, having no clear
expectation of victory nor exit plan nor clear world mandate of accord, Bush was
nonetheless determined to initiate war against Iraq and refused to allow any obstacle
stand in his way.

You would argue/prove the
critical argument of Plan of Attack, which arises
from the question Woodward poses, by referencing the facts about Powell, Cheney,
Scowcroft, the elder Bush, and George W. Bush as highlighted herein, along with other
personalities examined in the book.