We don't have so much of a problem directly in the Kent ports these days since so much has been introduced both the French and English ends in terms of heat-seeking scans in the lorries and much increased border patrol activity. It was bad about seven years ago, the place was teeming with people, they weren't allowed to work while their cases were being assessed so they were dossing around the town and there was a lot of bad feeling. I'm with Bobbi's earlier comment on this that genuine asylum seekers in fear of their lives should be allowed asylum across the nearest friendly border, but we are led to believe that a lot of people waiting in Calais at the moment are economic migrants which is not at all the same thing. When interviewed they say they are seeking work, not running for their lives.
The other point to remember is we are not the only country with this problem. The Canary Islands regularly have boatloads of people landing (or worse, not landing because they drown) trying to get away from North African countries. The economic migrant problem is massive. However, in the Canaries, they give them a meal and a medical check then put them on the first plane back (if they catch 'em).
If was interesting that immigration came in as the big No 1 on the Ed's recent election survey.