That&#x27;s fairly easy. Airports are closed right now, the old border posts, even though they have been un-manned for quite a while (but not everywhere, as I found out to my surprise a few months ago, a so called &#x27;spot check&#x27; was set up on one of the old border posts) can be easily re-established using military personel.<p>It&#x27;s a lot easier to re-establish something that was there before than it is to do it from scratch and this is more of a logistical problem (and a personel one) than one of technicalities about whether or not such a thing can be done. It&#x27;s not like France didn&#x27;t have a functioning border patrol a couple of years ago.