From ORAC's link
The senators in their letter noted it “could also be argued that directing military action to defend U.S. commercial shipping is within this power.” However, “most vessels transiting through the Red Sea are not U.S. ships, which raises questions about the extent to which these authorities can be exercised.”
“We support smart steps to defend U.S. personnel and assets, hold the Houthis accountable for their actions and deter additional attacks,” they wrote. “We further believe Congress must carefully deliberate before authorizing offensive military action.”
With the EU apparently arriving "soon" one wonders if the level of activity will decrease.
Iran's own limitations are discussed here.
https://foreignpolicy.com/2024/01/23...an-iraq-syria/
A summary: (Full article is worth a read)
Iran’s proxies can risk limited blowback from the United States and Israel because they have very little to lose.
Iran, on the other hand, would have much more to lose if it were to spark a direct conflict with the United States or Israel. Iran could not, for example, replicate the Houthis’ shipping blockade effort in the Strait of Hormuz. It could try, but the risk of sparking direct escalation with the United States, much less the strain that it would place on relations with China and its neighbors, would present significant risk.
Seeking to reduce risk is why Iran outsources much of the violence to its clients—and why its clients have taken the lead in military action against foreign adversaries during the current crisis. Funneling its strategic activities through proxies keeps the fight away from Iran’s doorstep and allows others to absorb the costs.
In the present context, as Iran and its proxies attempt to assert themselves as the chief countervailing force against Israel and the United States, they have few cards to play. That is especially true in terms of military action, where they are mostly limited to standoff strikes. They can fire at targets from a long distance and use the threat of such as coercion with neighbors and foes, but Iran and its clients cannot do much more. They cannot take their war to Israel or liberate Palestine by force.
Instead, they are limited to conducting provocative acts in an attempt to shape the political environment. For Iran, such acts signal both what it can do and the limits of what it’s willing to do for its cause.