Should President Obama end the war on terror?

He came to talk about the future, but the past keeps pulling him back.

President Obama outlined his vision for a revised American counterterrorism policy during Thursday's speech at the National Defense University in Washington, D.C., renewing his call to close the detention facility at Guantanamo Bay and announcing new guidelines to govern the use of targeted drone strikes on foreign soil.

Animating many of the president's proposals was a stated desire to "discipline our thinking and our actions" and to move America away from a "perpetual wartime footing" that has held sway for nearly 12 years, since Congress passed an Authorization to Use Military Force [AUMF] in the aftermath of the terrorist attacks on September 11, 2001.

The president pledged to "work with Congress" to "refine and ultimately repeal" the AUMF, warning that a strategy of "perpetual war - through drones or special forces or troop deployments - will prove self-defeating, and alter our country in troubling ways."

Simply put: While "our systematic effort to dismantle terrorist organizations must continue," the president said, "This war, like all wars, must end."

While Mr. Obama has spoken before about the need for a return to normalcy of sorts in how America views and responds to terrorist threats, rarely has he expressed that point so baldly and called for an outright "end" to the nearly-12-year old conflict.

But should the "war on terror," as we know it today, be drawn to a conclusion, given the continued threat posed by terrorists? And with the hypersensitivity attending public discussion on the issue, is it politically realistic to expect a declared end to the "war on terror" any time soon?

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The "big question here is whether the president's words translate into real policy or operational practice," said CBS News senior national security analyst Juan Zarate. "Ultimately, the threats, as they continue to morph, will dictate how willing we are to constrain [counterterrorism] power."

And the "political realities" of zero tolerance for terrorist attacks on the homeland will jeopardize "any attempts to limit our [counterterrorism] actions," added Zarate, also a former deputy national security adviser in the George W. Bush administration.

"The most important advance in the speech was the acknowledgement that the war will end at a foreseeable point in the future," former assistant secretary of state for public affairs P.J. Crowley told CBSNews.com. "This will require an unwinding of policies, authorities and tactics that have accumulated over the past dozen years."

But if the immediate reaction to Mr. Obama's speech is any indication, some in Congress are not so keen on abandoning America's post-9/11 counterterrorism policies, with several Republican senators blasting the president for what they fear is a premature pivot.

The president's speech "will be viewed by terrorists as a victory," Sen. Saxby Chambliss, R-Ga., said in a statement. "Rather than continuing successful counterterrorism activities, we are changing course with no clear operational benefit."

"To somehow argue that al Qaeda is quote, 'on the run,' comes from a degree of unreality that is really incredible," Sen. John McCain, R-Ariz., said after the president's speech Thursday afternoon, arguing that the terrorist syndicate is expanding, not contracting. "To somehow think we can bring the authorization of the use of military force to closure conflicts with the reality of the facts on the ground."

Crowley knocked Republicans for pushing a strategically and legally "unsustainable" policy, explaining, "We have invested significant powers in the president in a time of war, but to suggest that we will be engaged in war indefinitely fundamentally changes the Constitution, and I don't know that the American people want that and I'm not sure that the congress wants that either."

"Wars have beginnings, wars have endings, and wars have defined boundaries," he said. "Without specifics, then it's impossible to define success."

And a failure to augment America's counterterrorism posture, Crowley warned, could present dangers separate from the concerns voiced by GOP senators. "The concept of indefinite war plays into the al Qaeda narrative," he explained, noting the grievances that foreign populations have voiced about America's aggressively militarized counterterrorism policies. "When you project the prospect of indefinite war, that continues to suggest that the military will always be the primary instrument, and we have said many times that we can't kill our way out of this problem."

He added that the president "signaled very clearly that the challenge of terrorism is not going away," and that he is only striving to combat that terrorism in different ways as the threat evolves.

Michael O'Hanlon, a senior fellow at the Brookings Institution, echoed Crowley on that point, telling CBSNews.com in an email that the president's speech was "hopeful...in intent in aspiration, but also conservative in not abandoning any existing tools of warfare prematurely."

So where do we go from here? If the existing tools in the war on terror are increasingly difficult to situate within the 2001 authorization of military force, as Crowley and others argued, can Congress be expected to revise - or repeal outright - that authorization to accommodate evolving realities?

Sen. Bob Corker, R-Tenn., offered at least a glimmer of an opening to the president in a statement released before the speech, arguing that that the 2001 AUMF is "increasingly unrelated to current terrorist threats," and welcoming discussions with the administration and bipartisan members of congress on "how best to pursue necessary updates to the authorization for use of military force."

"I hope that Congress is open to a revision of the AUMF for a variety of reasons," Crowley said, "but if we're still at war, the American people need to know that we're still at war and they need to be assured that what we continue to do in various places around the world is consistent with both domestic and international law."

"The immediate response from members of Congress" on revising the AUMF "is not surprising but disappointing," Crowley said.

Zarate added that, while the president's "promise of eventual repeal is quite significant," it "will never be done in this term."

And as the promise of a long, hard slog awaits the president and those who support his push to pull Americans back from the fever pitch of a perpetual "war on terror," some argued that an abundance of patience might be in order.

"The president suggested that at a point, the war against al Qaeda or the war on terror will end just like all wars eventually end," Crowley said. "He didn't say it would be tomorrow."