Iran is the number one threat in the U.S. Central Command (CENTCOM) area of responsibility, even though turmoil continues in nations such as Syria, Egypt, Afghanistan, Pakistan and Iraq, Marine Gen. James Mattis told the Senate Armed Services Committee (SASC) recently.

“Despite significant economic sanctions and increased diplomatic isolation within the global community, Iran continues to export instability and violence across the region and beyond,” Mattis said in prepared remarks at the SASC posture hearing.

Almost exactly a year ago, Mattis told the same forum nearly the same thing: “Iran poses the single greatest threat to U.S. interests and to our friends and stability in the region, and poses a global threat through its world-wide proxy network as recent attacks have demonstrated.”

Senators continue to express their concerns about the Iranian drive to acquire nuclear weapons and spread its influence in the Middle East.

SASC Chairman Sen. Carl Levin’s (D-Mich.) opening remarks also reflected concerns he stated a year ago: “I believe most of the members of this Committee share President Obama’s view that all options– including military options–need to remain on the table and that preventing Iran from acquiring a nuclear weapon is not only our policy, but that we are determined to achieve it.”

Levin also previewed Mattis’ assessment that Iran continues to expand its threat network promoting violence across the region and provide financial and materiel support.

Iran apparently also has global connections–to nuclear technology proliferator North Korea, Mattis said, but couldn’t reveal more in an open hearing.

Senators were interested if the intelligence CENTCOM was receiving was adequate. Mattis said over his 40 plus years he has never enjoyed the level of intelligence and anticipation he’s been able to achieve, calling it “phenomenal.”

There was a caveat, though: Iran’s nuclear program takes place in a closed country, virtually a police state with strong denial and deception capabilities, where decisions can be made by within a small group that sometimes is the hardest to find out.

While Sen. John McCain (R-Ariz.) questioned if military budget woes would cause CENTCOM to change strategy, Mattis said yes, strategy would change, but he also sent a clear message: “I don’t want the enemy to feel brave right now. I can still deal with him in my region.”

The fact that financial belt tightening caused the U.S. Navy to stop an early February Middle East deployment of the USS Harry S. Truman (CVN-75) should not offer an opening to those who wish harm to the United States, he said.

Mattis said carrier groups obviously reassure friends and deter Iran, “but I believe a strong statement of political will and the forces I have there right now give Iran pause.”

The Navy has kept two carrier groups in the Persian Gulf as Iran since 2010 has repeatedly threatened to close the Straits of Hormuz, a vital oil shipping route.

Mattis said negotiations should continue, as should gathering partners and allies for a larger coalition against Iran’s nuclear ambitions, while recognizing their legitimate security interests. But “I requested and received additional forces…to reassure friends we mean business.”

Sen. Lindsay Graham (R-S.C.) saw two options on Iran: “Bring them to their senses, which is to stop developing a nuclear weapon capability or bring them to their knees so they can’t develop a nuclear weapon capability.”

Mattis agreed.

“As to the second option, do we have the capability to bring them to their knees,” Graham asked.

After a protracted silence, Mattis said, “Absolutely, senator.” He added, “I would still say, on ‘bring to their senses’ between economic sanctions, diplomatic isolation and encouragement of behavior that does not cost them such a degree of political support that they end up losing power there may yet be a way to bring them to their senses on a purely cost benefit ratio.”

Lindsay kept pushing: “I hope you’re right but if that doesn’t work the only option left is to bring them to their knees, do you agree?”

“Yes sir,” Mattis said. “There are a number of means to do that perhaps even short of open conflict.” But certainly that’s one of the options I have to have prepared for the president.”

About the same time across town at the Pentagon, Defense Secretary Chuck Hagel told Israeli Minister of Defense Ehud Barak President Obama is committed to preventing Iran from obtaining a nuclear weapon, and all options are on the table.

The readout of the meeting said that Hagel said the United States continues to believe there is still time to address this issue through diplomacy, but that window is closing.