"There is greater realization in the Iraq government that we should not shy away from coming and asking for some help and assistance," Zebari told reporters Friday in Washington.
He described U.S. interest in Iraq after the 2011 troop withdrawal as "indifferent, completely" but said that seemed to shift as the White House realized al-Qaida's resurrection there.
"Recently I noticed, and during this visit specifically, there is a renewed interest because of the seriousness of the situation and the challenges," Zebari said. "I think that is because of the threat of terrorism, the threat of the renewal of al-Qaida and its affiliates has become a serious, serious concern to the U.S."
The American troops left Iraq in December 2011 as required under a 2008 security agreement. Both countries tried to negotiate plans, but failed, to keep at least several thousand U.S. forces in Iraq beyond the deadline to maintain security. But the proposal fell through after Baghdad refused to give the troops immunity from legal charges, as Washington demanded.
Nearly 4,500 U.S. troops were killed, and American taxpayers spent at least $767 billion during the nearly nine years of war in Iraq.
Zebari attributed the insurgency's comeback to its partnerships with al-Qaida fighters in neighboring Syria and outlawed Baath Party extremists in Iraq's south. Intelligence experts have described the terror group's footing in Iraq and Syria as a new al-Qaida hub in the Mideast, one that has sought for years to underscore Baghdad's inability to protect its people.
Most of the attacks in Iraq target government officials, security forces and Shiite pilgrims and neighborhoods. A senior U.S. administration official this week said the number of suicide bombings in Iraq has more than tripled in recent months, and it's believed that most of the attackers are coming from Syria.
"The security situation in Iraq is deteriorating rapidly and is of significant concern," Sen. Bob Corker, top Republican on the Senate Foreign Relations Committee, said this week after meeting Iraqi Prime Minister Nouri al-Maliki and other senior Iraqi officials during a trip to Baghdad and Irbil, the Kurdish capital in Iraq's north.
"A United States foreign policy that does not recognize this will be very problematic," said Corker, R-Tenn.
Distracted by a civil war in Syria, a policy pivot to Asia, growing extremism in North Africa and Iran's nuclear ambitions, the White House put Iraq on the back burner.
Egypt, once reliably stable, has disintegrated over deadly street riots and attacks that killed more than 600 people this week during protests over the ouster of Egyptian President Mohammed Morsi. Jordan, a key U.S. ally, is threatening to collapse under financial strain caused, in large part, by more than 1 million refugees who have crossed into the country from Syria. The U.S. is also leading peace talks between Israel and Palestinian authorities, and watching a growing threat from al-Qaida in the Arabian Peninsula in Yemen. A threat from al-Qaida led to the closing of 19 diplomatic posts across the region last week.
"That's a pretty large agenda," said Jon Alterman, a Mideast expert at the Center for Strategic and International Studies in Washington. "Iraq is no longer viewed as central to everything the U.S. cares about in the Middle East. But Iraq is still relevant to a wide range that the U.S. cares about."
In the 20 months since the troop withdrawal, the U.S. has sought to stay out of Iraqi affairs and engage with its government as Washington would with any other nation. A majority of Americans agreed with that approach, and 58 percent of U.S. adults said in a Washington Post-ABC poll taken in March that the Iraq war had not been worth the fight.
Still, U.S. officials say they remain actively involved in Iraq, and have quietly stepped up diplomatic efforts since March, when U.S. Secretary of State John Kerry visited Baghdad for the first time in his new post. They largely have focused on ensuring Sunni Muslims are included in Iraq's Shiite-led government, and have urged Shiite leaders to resist retaliating to the Sunni insurgency's attacks in what State Department spokesman Mike Lavallee described Friday as "quite intensive" diplomacy.
But the engagement also has centered on making sure Iraq's government remains independent from the Shiite government in Iran and staying out of the civil war in Syria, where Sunni Muslim rebels are seeking to overthrow Syrian President Bashar Assad, an Alawite. Alawites are an offshoot of Shiite Islam.
Washington has repeatedly chastised Baghdad for allowing Iranian planes to fly weapons over Iraqi airspace to Assad's forces, a violation of U.N. sanctions. Zebari said Friday that Baghdad has inspected at least 15 flights to Syria since March, and did not find any fighters or weapons. He said most of the inspected flights were from Iran or Syria, but also included planes form North Korea and Armenia.
But Iraq is grappling with its own sectarian tensions that experts say could spawn civil war.
In a report released this week, the Brussels-based International Crisis Group described boiling frustrations among Iraqi Sunnis for being politically sidelined and, in at least one deadly raid in April, targeted by security forces.
"A new wave of violence is engulfing Iraq," the report concluded. "Citizens and politicians alike express fears of a return to sectarian strife."