Iran's military starting Thursday issued a warning to ships at sea that it planned to run a drill starting this weekend which is to include live firing in the Strait of Hormuz, potentially disrupting traffic through a waterway which sees 20% of all the world's oil pass through it.

This prompted a US warning in response, given US forces are also in the region - but quite a bit further away. On Iran's two-day live-fire naval exercise, US Central Command (CENTCOM) said it will not tolerate any unsafe behavior which threats US forces, and somewhat awkwardly called on IRGC forces to operate professionally.

"We will not tolerate unsafe IRGC (Islamic Revolutionary Guard Corps) actions including overflight of U.S. military vessels engaged in flight operations, low-altitude or armed overflight of U.S. military assets when intentions are unclear, highspeed boat approaches on a collision course with U.S. military vessels, or weapons trained at U.S. forces," CENTCOM said in its statement Friday.

"US forces acknowledge Iran's right to operate professionally in international airspace and waters," it added, and noted that "any unsafe and unprofessional behavior near U.S. forces, regional partners or commercial vessels increases risks of collision, escalation, and destabilization."

Meanwhile the US forces build-up continues in the region:

A U.S. Navy destroyer made a port visit to the southern Israeli city of Eilat on Friday. The USS Delbert D. Black is one of six U.S. destroyers now in the Middle East, along with an aircraft carrier and three other combat ships.

China and Russia have just sent a big, resounding message to Washington in dispatching their own naval assets which have been sailing near Iranian vessels over the last several days - though this appeared for a prior, pre-planned joint drill.

According to the details of this prior joint exercise:

Ahead of the exercises, Iran issued a Notice to Airmen (NOTAM), warning of live-fire military activity in the airspace surrounding the Strait of Hormuz.

According to the notice, military firing activity was conducted between January 27 and 29 within a five-nautical-mile radius. The airspace—from ground level up to 25,000 feet—was designated as restricted and hazardous throughout the duration of the maneuvers.

In parallel, the three countries just deepened trilateral ties:

In a dramatic geopolitical development... Iran, China and Russia formally signed a comprehensive strategic pact, marking one of the most consequential shifts in 21st-century international relations. While the full text of the agreement is being released in stages by the three governments, state media in Tehran, Beijing and Moscow have acknowledged the ceremony and described it as a cornerstone for a new multipolar order.

The pact comes against the backdrop of decades of growing cooperation between these three states. Iran and Russia earlier concluded a 20-year Comprehensive Strategic Partnership Treaty designed to deepen economic, political, and defense ties, and to blunt the impact of Western sanctions — a treaty that was signed in January 2025 and entered into force last year.  Meanwhile, Iran and China have been bound by a 25-year cooperation agreement first signed in 2021, aimed at expanding trade, infrastructure, and energy integration.

Still, none of this has deterred the ongoing Pentagon build-up in the Middle East with an eye on Iran. One thing the White House should be able to perceive, however, is that any military action against Tehran is going to clearly be much more complex, and harder, than some one-off mission in Venezuela.

The potential for massive blow-back and for things to go seriously awry is much greater in the case of the Islamic Republic.