President Bush is learning that there are limits to presidential power.

Since the 9/11 terrorist attacks, the president has used his commander-in-chief hat to expand his imperial reach beyond what the U.S. Constitution has prescribed.

He has wiretapped Americans without court permission; he has grabbed Iraqis and Afghans in their own countries and shipped them to Guantanamo Bay, Cuba, where some have been held in limbo for more than four years.

His overreach was spurred by Vice President Dick Cheney. That would be the same vice president who famously argued against Sen. John McCain's proposed ban on torture and lost.

Cheney has stressed he believes that the Watergate scandal and the Vietnam War led to an encroachment on presidential powers.

The vice president sure has that right -- but he really shouldn't go there. President Nixon was forced to resign because of his abuse of power in the Watergate scandal. President Johnson's involvement in the unpopular Vietnam War forced him to renounce his hopes for re-election.

The incumbent president should take note of a story in The Boston Globe to the effect that Bush has issued "signing statements" when he put his signature on 750 new laws. Those statements amount to assertions that he can ignore those laws if they don't conform with his own interpretation.

For example, when he signed the bill banning torture, he issued a signing statement that essentially said he could bypass the ban.

He also has issued an order to government agencies declaring that they should adhere to his interpretation of the law.

Bush has to be disabused of the idea that he can rule by fiat in the struggle against terrorism.

Fortunately, the U.S. Supreme Court cut him down to size when it ruled last week that Bush's establishment of military commissions to determine the fate of the Guantanamo detainees is unconstitutional.

In a 73-page opinion, Justice John Paul Stevens wrote for the 5-3 majority and declared: "The executive is bound to comply with the rule of law that prevails in this jurisdiction."

The decision also held that the Geneva Conventions on humane treatment of prisoners applies and is enforceable in federal courts.

The high court told Bush he could abide by the normal rules of military courts-martial or go to Congress and ask for legislative approval for military tribunals.

Two years ago, the Supreme Court ruled that Bush did not have a blank check to deny the hundreds of prisoners at Guantanamo some minimal rights.

White House press secretary Tony Snow said Bush is reviewing his options. Wouldn't he best serve the country's values by acknowledging that normal legal protections will now apply to the detainees?

The court noted the flaws in the failure to guarantee the defendant the right to attend his trial; the prosecution's ability to introduce hearsay evidence, and evidence obtained through coercion.

The dissenters on the court were the usual suspects: Justices Antonin Scalia, Clarence Thomas and Samuel Alito. The trio called the ruling "untenable" and "dangerous."

Thomas said the court had disregarded the commander in chief's "wartime" powers.

It was not the first time the court has slapped down a president. In 1952, the court rejected President Truman's seizure of the steel mills during the Korean War. In 1974, the court ordered Nixon to turn over the Watergate tapes.

Bruce Fein, a Reagan administration official, said the ruling shows Bush is "bound by treaties and statutes."

Imagine that!

Helen Thomas is a columnist for Hearst Newspapers. E-mail to: helent@hearstdc.com.

© 2006 Hearst Newspapers

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