I don’t know about you, but I find on occasion that there’s nothing more relaxing than to curl up with some good reading material. Well, the other day I was getting cozy with my favorite Geneva Conventions on the laws of war, and to my surprise I came across an annex to the conventions detailing the ins and outs of what’s legal and what’s not legal in the conduct of warfare at sea. How about that?

The document is fetchingly titled The San Remo Manual on International Law Applicable to Armed Conflicts at Sea, 12 June 1994.

Well, here’s what I found out: First of all, blockades are legal. A country that is at war is legally entitled to impose a blockade on the opposing party in order to cut off its supply of materials necessary for war.

You won’t be surprised to learn that neutral vessels on the high seas are almost always protected from attack by belligerents. What I didn’t know, and I bet most of you didn’t, either, is that vessels suspected of breaching a blockade may be stopped, boarded and inspected on the high seas by the party imposing the blockade. And if they resist search or capture, they may be attacked.

The manual actually spells this rule out twice, in two separate paragraphs, perhaps to catch the attention of people who might be under the misapprehension that attacking a neutral vessel on the high seas is necessarily illegal, or that passengers on a ship have a natural right to fight back when their ship is boarded by a military party enforcing a blockade. It isn’t, and they don’t.

(67.) Merchant vessels flying the flag of neutral States may not be attacked unless they:

(a) are believed on reasonable grounds to be carrying contraband or breaching a blockade, and after prior warning they intentionally and clearly refuse to stop, or intentionally and clearly resist visit, search or capture;

Second:

(98.) Merchant vessels believed on reasonable grounds to be breaching a blockade may be captured. Merchant vessels which, after prior warning, clearly resist capture may be attacked.

Now, there are certain rules binding on the party that imposes the blockade, and they’re worth noting carefully:

(148.) Contraband is defined as goods which are ultimately destined for territory under the control of the enemy and which may be susceptible for use in armed conflict.

(149.) In order to exercise the right of capture referred to in paragraphs 146(a) and 147, the belligerent must have published contraband lists. The precise nature of a belligerent’s contraband list may vary according to the particular circumstances of the armed conflict. Contraband lists shall be reasonably specific.

(150.) Goods not on the belligerent’s contraband list are ‘free goods’, that is, not subject to capture. As a minimum, ‘free goods’ shall include the following:

(a) religious objects;

(b) articles intended exclusively for the treatment of the wounded and sick and for the prevention of disease;

Now it gets really interesting. Read this subparagraph, and pay attention to the exception, which I have conveniently marked off in italics (in honor of San Remo):

(c) clothing, bedding, essential foodstuffs, and means of shelter for the civilian population in general, and women and children in particular, provided there is not serious reason to believe that such goods will be diverted to other purpose, or that a definite military advantage would accrue to the enemy by their substitution for enemy goods that would thereby become available for military purposes;

Here’s what I get out of this: Hamas, as I understand it, considers itself to be at war with Israel, and Hamas governs Gaza. Presumably, then, Israel is entitled to impose a blockade on Gaza to keep out tools of war, including food, clothing and means of shelter that might give the enemy a military advantage (with certain limitations — “substitution for enemy goods” etc.).

The flip side is that the blockading party must publish a list of contraband items. Anything not on the list is not subject to blockade. As I understand it, Israel had published a list of what is permitted, not what is forbidden, until it changed policy in the wake of the flotilla incident.

So where does that leave us? In the clear? Arguably. Busted on a technicality? Maybe. Piracy? I don’t think so.

Apparently the annex was adopted at a conference convened in 1994 in San Remo, Italy, by the International Institute of Humanitarian Law, under the auspices of the international Committee of the Red Cross, which administers the Geneva Conventions. I think that’s why it’s called the San Remo Manual etc.