At least four Russian cruise missiles, headed for Syria, have reportedly crash-landed in Iran, Pentagon sources tell CNN and other outlets.

Pentagon sources tell CNN So far neither Russian nor Iranian sources have confirmed the incident, though Iran's semi-official Fars News Agency is carrying the story (but crediting CNN).

It is not known whether the missiles detonated or whether there are any casualties. Iran has enough empty space that it's possible the missiles crashed harmlessly.

Russia has been launching cruise missiles from its fleet in the Caspian Sea, firing them over Iran and Iraq toward Syria, so northwest Iran is on their normal flight path. This state media video shows earlier launches and their path:

Russia's high-tech military gear is just not that great

For all Russia's military might — its force, one of the largest in the world, has been modernizing in recent years — its higher-tech equipment such as cruise missiles has long lagged behind Western standards.

Cruise missiles are particularly difficult technology, flying many hundreds of miles at high speed, often automated. Early American cruise missiles also crashed often, requiring many years of testing and refining before they worked as well as they do now, and the Russian land-attack cruise missiles here are recently developed.

This is a helpful reminder of a fact that is often forgotten in Washington but is remembered all too well in Moscow: The Russian military is formidable, but it is a generation or more behind American forces. After a week of hyperventilating American coverage of Russia's Syria intervention, this should be a reality check.

The Washington Post's Andrew Roth and Thomas Gibbons-Neff, a few days, had this quote in a story explaining why Russia's military is unlikely to turn the tide in Syria:

"We are basically novices in this type of war," said Ruslan Pukhov, a defense expert and director of the Moscow-based Center for Analysis of Strategies and Technologies, in an interview. "And when you are a novice, you are doomed to commit some kinds of mistakes. Hopefully not deadly ones, but obviously there is a risk of casualties."

It is also a worrying indication that inaccurate Russian launches risk increasing already sky-high civilian casualties in Syria.

A big question: Will this have political ramifications in Iran?

Iran and Russia are on the same side in Syria, both supporting Syrian leader Bashar al-Assad, but there have been growing reports of tension and competition between them over Syria's future. And there is a long history of bitterness between Russia and Iran, the latter of which has not forgotten Russia's imperialist history in its country, nor Russia's support of crippling UN sanctions.

One thing that will be worth watching, then, is whether this incident uncovers or provokes any Iranian backlash against Russia. Will this be brushed off as an innocent mistake, or will it prompt public criticism from Iran's often-noisy political system? So far, there's no noise out of Tehran one way or the other, but the possibility of Iran-Russia tension over Syria is worth looking out for.

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