Over the weekend the US closed many of its embassies in the Middle East and North Africa as a result of what was described as a serious al Qaeda threat.

Given the number of times US embassies have come under attack in the last decade or so, and certainly in the post-Benghazi era, it would seem hard to argue against such a dramatic move. Indeed, it says something that these days such precautions don't really seem that dramatic any more.

The problem is, they should. Closing all of your embassies in the Middle East raises the question of whether it is even worthwhile having embassies anymore.

It is not just the act of closing an embassy for security reasons that is an issue. Anyone who has had a meeting at an American embassy in the Middle East or South Asia knows the experience of going through multiple layers of security. The embassies have come to resemble fortresses and bunkers.

This is both a symbolic and a practical matter. While I would not want to make too much of this, the size and disposition of an Embassy – whether it is open and accessible or hunkered down – does say something to the locals about the country the embassy represents. But far more serious is the practical problem caused by the pre-occupation with security, in particular the fact that diplomats leave their embassies a lot less than they used to.

You might argue that this only really happens in countries like Pakistan or Egypt where the security situation warrants it. In Australia, for example, American diplomats move around freely. But it is precisely in countries like Pakistan and Egypt, where there are problems in the bilateral relationship or where the political situation is in flux and it is difficult to understand what's going on, that you need embassies and where diplomats need to be out and about.

This is not just a recent development. I remember when I served with the Australian mission in Tel Aviv in 2000 after the outbreak of the second Intifada, my American colleagues would constantly lament how onerous and time consuming it became to organise travel to the West Bank and that when they eventually did go they were accompanied by so much security that it was intimidating for the locals.

Nor is it just an American story. Some of my former DFAT colleagues have complained of how security restrictions limited their ability to do their job in the post-9/11 era.

If, as a diplomat, you cannot actually spend time travelling in your host country and if you can't develop strong relationships with the locals, you might as well pack up and go home. You cannot effectively represent the country from which you have come, nor can you really develop an understanding of the country to which you are posted.

You could argue that maintaining such levels of contact are not worth a diplomat's life. Indeed, by closing embassies, even temporarily, and by bunkering them deep in multiple security perimeters this is effectively the judgement you are making. But if that is the case, then we need to ask what purpose embassies really serve anymore. Why have anyone in the country at all?