President George W. Bush has made broad use of his executive powers: authorising warrantless wiretaps, collecting telephone records on millions of Americans, holding suspected terrorists overseas without legal protections. His administration even is considering using the military to patrol the US border.

Congress is on notice from the president that he will not enforce parts of legislation he believes interfere with his constitutional authority.

These are extraordinary times, for sure, and the president says he is acting to safeguard the country. But Democrats and some Republicans, along with human rights activists and legal scholars, suggest Bush has gone too far in stretching presidential powers.

“I do think the president has pushed the envelope,” said Georgetown University political scientist Stephen J. Wayne. “He seems so determined for another act of terrorism not to occur on his watch that he has forgotten the constitutional protections that most Americans value as highly as they value their security.”

Bush is using a variety of techniques and strategies to maximise his power — at the expense of Congress, some say. It’s a course, critics suggest, that both he and Vice President Dick Cheney have pursued since they took office in January 2001.

Administration officials insist they have acted within constitutional limits, citing added flexibility that comes during a time of war.

The disclosure last week that the National Security Agency is building a database of domestic telephone numbers has touched off an intense debate about whether the administration and phone companies are undermining people’s privacy rights.

Expressions of concern came from some prominent Republicans, including House Majority Leader John Boehner, and added to earlier questions about the NSA’s domestic eavesdropping programme.

These once-covert programs pose potential trouble for the president’s nomination of Air Force Gen. Michael Hayden to be CIA director. Hayden oversaw both programmes as NSA director from 1999-2005.

“Everything that the agency has done has been lawful,” Hayden asserted last week as he visited the offices of the senators who will vote on his nomination.

Senator Arlen Specter, the Republican chairman of the Senate Judiciary Committee, says his committee will scrutinise Hayden’s role in both the NSA’s phone data bank and the eavesdropping programme.

Former CIA Director Stansfield Turner is among those critical of the administration’s eavesdropping programme and Hayden’s oversight.

“I’m concerned that he had a role in wiretapping American telephones without warrants. I interpret that, if it happened, as against the law. Apparently, the president and others interpret it otherwise,” said Turner, who was CIA chief in the Carter administration.

In projecting his powers widely, Bush has made extensive use of statements that accompany the signing of a bill into law. These statements claim a presidential prerogative not to enforce parts of the legislation that he deems to encroach on executive authority. He has issued hundreds of such statements.

Among provisions he has challenged is a requirement to give detailed reports to Congress about his use of anti-terrorism laws contained in the Patriot Act and about a ban on torture.

“The president apparently believes, based on a number of recent statements and policy directives, that anything he approves is automatically legal,” said Stephen Cimbala, a Pennsylvania State University professor who studies national security issues. — Associated Press