WASHINGTON >> The death of Osama bin Laden sparked euphoria and national pride. But most Americans won’t see any tangible difference.

The war on terror goes on. Airport security remains unchanged — take your shoes off and ditch the shampoo. Expect more security at major events. And the tax burden related to security won’t abate anytime soon.

Dead or alive, the mastermind of Sept. 11 transformed the United States, and vigilance remains vital — especially in the short term just after his death, experts say.

“Over the long arc of the war against al-Qaida, this is a very big important deal,” said Matt Bennett, vice president at Third Way, a centrist Democratic think tank. But “will Americans feel this in a direct way? Probably not for a very long time.”

Since the 2001 attacks, the United States has spent roughly $1.4 trillion on the wars in Iraq and Afghanistan, including about $28 billion to boost homeland security.

“The attacks are still going on against our troops. The networks are still operating. Al-Qaida is still operating,” said Senate Intelligence Chairwoman Dianne Feinstein, D-Calif. “So it goes on.”

Sen. John Cornyn, R-Texas, echoed that. “It’s not as if the threat of terrorism goes away. … We can’t let our guard down.”

For most Americans, the only direct interaction they have with security is when they fly. And even with the al-Qaida leader gone, airlines remain a tempting target for his followers.

Anyone who resents a pat-down can blame bin Laden. But don’t expect the hassles to diminish now that he’s dead.

The 3-ounce limit on carry-on liquids is dictated by the amount of explosives needed to bring down an aircraft, for instance. For some passengers, the only difference traveling this week has been an extra dose of anxiety about retaliatory attacks.

“It was a little bit scary flying today,” said Debra Melott of San Angelo, Texas, arriving Tuesday at Reagan National Airport in Washington. As for security protocols, she said, “Americans have become accustomed to it. It does get to be a pain, but it is necessary.”

The Transportation Security Administration — created after the Sept. 11 attacks — has not announced any new procedures in the wake of bin Laden’s death.

The agency said travelers will continue to see “physical bag checks, random gate screening, explosives detection technology, canine teams and behavior detection officers.”

At Reagan airport, Indah Oei, a Garland, Texas, resident who flies a half-dozen times per year, said the day she expects to keep her shoes and belts on at the security checkpoint is the day “when there are no more terrorists.”

“Although it is a tremendous victory that Osama bin Laden was removed and killed, the cause of Islamic terrorism unfortunately lives on,” said Sen. Susan Collins of Maine, the top Republican on the Homeland Security Committee. “I do not see us able to greatly scale back our security efforts.”

Airlines say efficiency is the key to making security lines tolerable.

“Unfortunately, transportation and aviation are still in that high-profile category,” said Steve Lott, a spokesman for the Air Transport Association. “I don’t think that anyone believes that threat is going to be eliminated overnight.”

Part of the challenge is the decentralization of al-Qaida.

Bin Laden’s death makes the world “a little safer,” CIA Director Leon Panetta told NBC News on Tuesday, “But I also don’t think we ought to kid ourselves that killing Osama bin Laden kills al-Qaida. … They’re still going try to attack our country. We have to continue to be vigilant.”

While bin Laden supervised planning for the 9/11 attacks, more recent plots were merely inspired by his ideology.

Senate Homeland Security Committee Chairman Joe Lieberman, I-Conn., appealed for public vigilance, citing concerns about a retaliatory attack from “a so-called lone wolf, a single individual who has been radicalized.”

Such jihadists may lack training or resources, but they are notoriously difficult to spot.

In Congress, a handful of lawmakers in both parties have already begun agitating for a more rapid withdrawal from Afghanistan. But congressional leaders — and President Barack Obama — view that as premature.

Anyone hoping for a short-term “peace dividend” may be disappointed.

Rep. Michael McCaul of Texas, a top Republican on the House Homeland Security panel, said bin Laden’s death makes an accelerated drawdown from Afghanistan more palatable, though.

“We have to start transitioning,” he said. “There are other ways to deal with the al-Qaida threat than having a huge military presence in Afghanistan for decades.”

If anything, national security officials foresee a potential for retaliatory attacks from al-Qaida or its supporters.

James Carafano, a top terrorism expert at the conservative Heritage Foundation, said the sums spent on homeland security are relatively modest. And he noted that at least 38 plots have been foiled since Sept. 11, 2001.

Despite complaints about a “fortress state,” much of what the Department of Homeland Security does — border security, counterterrorism and such — isn’t new.

“People have been trying to kill us,” Carafano said, and that won’t change overnight. “Every generation has its terrorist threats.”

At the National Security Network, executive director Heather Hurlburt said bin Laden’s death makes it easier for the public to comprehend the decentralized nature of the threat — and the fact that terrorists cannot deal a “mortal blow to the functioning of our society.”

That makes this a good time to reopen a national debate over the proper level of security — how much drag on the economy people are willing to tolerate, and how much pressure on civil liberties.

Israel, she noted, has intense airport security “and you don’t have to take your shoes off.”

“Nothing ends magically this week. The level of vigilance shouldn’t subside,” she said.

Fred Burton — a former counterterrorism agent who oversaw the capture of Ramzi Yousef, mastermind of the 1993 World Trade Center bombing — noted that the threat persisted even though “bin Laden lost day-to-day command of the organization back when we invaded Afghanistan.”

Public transportation in New York and Washington remain vulnerable targets, he said. But a strategic, mass casualty attack akin to Sept. 11 would be unlikely.

“Your average person can’t buy 1,000 pounds of explosives in our post-9/11 world … without raising eyebrows,” said Burton, a vice president at Stratfor, an Austin, Texas-based global intelligence company. But “that doesn’t mean they’re not still capable of killing.”

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Staff writer Matthew Huisman contributed to this report.