Washington CNN  — 

The US has strengthened its military posture consistently in the Middle East over the last year following the breakout of the war between Israel and Hamas, with tensions increasing further in the days after Israel launched its operation against Hezbollah.

Twice this year, US forces in the region have assisted Israel in intercepting an attack by Iran. On October 1, two Navy destroyers in the eastern Mediterranean shot off roughly 12 interceptors against Iranian missiles — of which officials said approximately 200 were fired toward Israel.

Defense Secretary Lloyd Austin said in a statement that he was “proud of the skill and the bravery” of the US forces who took part in the interception of Iran’s attack.

“We will never hesitate to protect our forces and interests in the Middle East, and to support the defense of Israel and our partners in the region,” he said.

As of August, there was a total of roughly 40,000 US troops in the Middle East. The presence of US firepower to the region aims to send a clear deterrence message and to defend against attacks on Israel or US forces if necessary. There have been frequent low-level attacks on US forces in Iraq and Syria by Iranian-backed groups over the last year, though they have mostly slowed over the past several months.

Still, the US is aiming to make it crystal clear that wider attacks would provoke a major response.

Austin announced in early August that he was sending the USS Abraham Lincoln Carrier Strike Group to the region; it arrived later that month.

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The strike group consists of thousands of sailors and Marines, spanning across three destroyers and a carrier air wing. As of early October, the Lincoln aircraft carrier, its air wing — which is made up of eight squadrons — and the USS O’Kane, one of the guided-missile destroyers in the strike group, were in the Gulf of Oman. The USS Spruance and USS Frank E. Petersen Jr., also both guided-missile destroyers that are part of the strike group, were operating in the Red Sea.

In addition to the firepower brought by the Lincoln strike group, the Navy has a number of other destroyers and capabilities in the region.

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The Wasp Amphibious Ready Group (ARG) and 24th Marine Expeditionary Unit (MEU) Special Operations Capable are made up of roughly 4,500 sailors and Marines. In addition to the USS Wasp, an amphibious assault ship, is the USS New York, an amphibious transport dock ship, and the USS Oak Hill, a dock landing ship.

The MEU is one of the US’ primary crisis response forces; one of its mission essential tasks is its ability to conduct a non-combatant evacuation operation of American citizens. The 24th MEU conducted such an operation years ago in 2006, bringing thousands of Americans out of Lebanon during the conflict between Israel and Hezbollah.

As of early October, the ARG MEU — as well as the USS Bulkeley, Cole, and Arleigh Burke –were operating in the Eastern Mediterranean. The USS Murphy, Indianapolis, and Stockdale were operating in the Red Sea.

In addition to the numerous Air Force capabilities already in the region — including fighters, transport aircraft, and tankers — the Pentagon said Sunday that more air support capabilities were heading to the Middle East.

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Deputy Pentagon press secretary Sabrina Singh said Monday that would include F-22, F-16, F-15E and A-10 aircraft and associated personnel, totaling upwards of “an additional few thousand” more forces. US Central Command said Tuesday that one aircraft squadron had already arrived in the region with three more on the way.

Meanwhile, the Army has thousands of conventional ground forces in the Middle East as well as various air defense and artillery capabilities, including Patriot missile systems, counter-drone systems, and High Mobility Artillery Rocket Systems (HIMARS).