The Iraq War is Illegal

Does W have the authority under the US Constitution to increase troops in Iraq?

The short answer: No.

First, this is not a war. Under the Constitution, only Congress can declare war, and none has been so declared.

W invaded Iraq under the pretext of the Joint Resolution entitled "Authorization for the Use of Military Force Against Iraq". The use of the US military was authorised only under 2 scenarios:

The Congress of the United States supports the efforts by the President to--
(a) strictly enforce through the United Nations Security Council all relevant Security Council resolutions applicable to Iraq and encourages him in those efforts; and
(b) obtain prompt and decisive action by the Security Council to ensure that Iraq abandons its strategy of delay, evasion and noncompliance and promptly and strictly complies with all relevant Security Council resolutions.

Now, neither of these ever existed. Certainly, no one can reasonably argue that they currently exist.

Therefore, at this time, W does not have any Congressional authority to have troops in combat Iraq, as far as I can tell.

The War Powers Act allows a president to use the US military in combat without a Constitutional declaration of war; however, the President is required to follow certain procedures:

Sec. 4. (a)
In the absence of a declaration of war, in any case in which United States Armed Forces are introduced--
(1)
into hostilities or into situations where imminent involvement in hostilities is clearly indicated by the circumstances;
(2)
into the territory, airspace or waters of a foreign nation, while equipped for combat, except for deployments which relate solely to supply, replacement, repair, or training of such forces; or
(3)
(A)
the circumstances necessitating the introduction of United States Armed Forces;
(B)
the constitutional and legislative authority under which such introduction took place; and
(C)
the estimated scope and duration of the hostilities or involvement.
Sec. 4. (b)
The President shall provide such other information as the Congress may request in the fulfillment of its constitutional responsibilities with respect to committing the Nation to war and to the use of United States Armed Forces abroad.
Sec. 4. (c)
Whenever United States Armed Forces are introduced into hostilities or into any situation described in subsection (a) of this section, the President shall, so long as such armed forces continue to be engaged in such hostilities or situation, report to the Congress periodically on the status of such hostilities or situation as well as on the scope and duration of such hostilities or situation, but in no event shall he report to the Congress less often than once every six months. [emphasis OZ]
W has not reported to Congress on the US military in Iraq in 11 months.
What happens after this 6-months report?
SEC. 5. (b)
Within sixty calendar days after a report is submitted or is required to be submitted pursuant to section 4(a)(1), whichever is earlier, the President shall terminate any use of United States Armed Forces with respect to which such report was submitted (or required to be submitted), unless the Congress (1) has declared war or has enacted a specific authorization for such use of United States Armed Forces, (2) has extended by law such sixty-day period, or (3) is physically unable to meet as a result of an armed attack upon the United States. Such sixty-day period shall be extended for not more than an additional thirty days if the President determines and certifies to the Congress in writing that unavoidable military necessity respecting the safety of United States Armed Forces requires the continued use of such armed forces in the course of bringing about a prompt removal of such forces.

Furthermore, W has called the legally-required timetable , and has expressly refused to comply with the legal requirement that he make a timetable for the use of the troops.

But Mr. Bush was emphatic in stating that the decision on troop levels will be made by American commanders and "not by artificial timetables set by politicians in Washington," reports CBS News correspondent Mark Knoller.

Therefore, W has no authority under the Constitution for troops to be in Iraq, he has failed to comply with the specific requirements of the War Powers Act, and is currently illegally sending 21,000 more troops to Iraq, and is currently waging an illegal war in Iraq.