99% of the immigrants in the last 13 years were allowed in under the EU agreement signed by the Tories.
Prior to the Border Agency we had no one checking who came in or out at our borders, at least we've now made a start doing that, but it'll be another 10 years before we get as good at it as the Yanks.... although that depends on the new computer system which will probably be finished in 3048 at a cost of £46Zillion over budget