Israel's clandestine battle with weapons smugglers
The announcement by Israel that it has seized a major shipment of weaponry heading to the Gaza Strip from Iran throws a spotlight on alleged ongoing attempts to arm militants there, and Israel's aim to thwart them.
It is not the first such shipment to be intercepted, but Israel says the armaments were of a much more advanced - and dangerous - kind than on previous occasions.
So how does this compare to previous Gaza arms interceptions?
The most famous episode is that of the Karine-A in January 2002. It loaded its cargo in Iran and was subsequently boarded by Israeli commandos, who found some 50 tons of weaponry on board.
Earlier shipments, the Israel Defense Forces (IDF) note, have comprised standard weaponry such as mortars, small-arms ammunition and medium-range rockets. The shipment on board the KLOS-C in March 2014 contained similar items but also the M-302 rockets.
Why is the Israeli navy operating so far from its own shores?
The Red Sea is the cockpit for a clandestine battle going on between Palestinian weapons smugglers, their backers and the Israeli military.
Israel monitors traffic there closely and is believed to have small but significant intelligence assets in the area.
Sudan is the focus of much of this alleged smuggling activity. In October 2012 four unidentified aircraft - presumed to be Israeli - attacked a warehouse or factory complex on the outskirts of Khartoum.
In April 2011 a prominent Hamas official believed to have been involved in weapons procurement for the Gaza Strip-based Palestinian organisation was killed by a missile-strike in Port Sudan.
The Sudanese authorities pointed the finger at Israel. In 2009 there were credible reports of a major arms convoy in the Sudan being hit from the air.
But why the Red Sea?
Sudan is believed by intelligence experts to be a key staging post for weaponry heading from Iran to Palestinian factions in the Gaza Strip.
US diplomatic cables revealed by Wikileaks show that as far back as January 2009 the US was urging Sudan to halt arms flights between Tehran and Khartoum.
In the March 2014 case - unusually - the Israelis say that the weaponry actually originated in Syria from where it was flown to Tehran.
It was then put on board the Klos-C at the Iranian port of Bandar Abbas.
From there it went to Um Qasr in Iraq, before heading back out of the Gulf and round to the Red Sea where it was intercepted.
The Israelis say that it was due to dock in Port Sudan, from where the weapons would have moved overland through the Sinai Peninsula and ultimately into the Gaza Strip.
If the shipment had got through, how would it actually have got into Gaza?
The new Egyptian authorities have closed down many of the smuggling tunnels from the Sinai Peninsula into the Gaza Strip and there is no love lost between the Egyptian military and Hamas.
However the chaos in the Sinai - where the Egyptian military is waging a bitter counter-insurgency struggle against a loose coalition of Jihadists and local criminal groups - means that Egypt probably cannot seal the border to the Gaza Strip as firmly as it might wish.
What threat could the weapons have posed?
The M-302 is a ground-to-ground rocket manufactured in Syria since the 1990s.
The basic missiles have ranges of between 90 and 115km (56 to 71 miles) although there are versions with almost double this range.
Hamas has had small numbers of longer-range missiles before. It fired five locally-manufactured M-75 rockets during the conflict with Israel in November 2012.
These have a range of up to 70km (43 miles).
Hamas is believed to have manufactured a few dozen of these weapons since then, but clearly the M-302 would give the organisation the ability to strike deep into Israel in addition to complicating the job of Israeli missile defences, because the area to be defended grows with the range of the missile.