I think it's a growing concern.
Some of our detection systems are contingent on the size of the vessel, so one of the new areas of concern is what we call go-fast boats, the tiny little whalers that can be very destructive, but are not required by law to have a vessel identification system, nor do I think that's necessarily practical or possible to do. Maritime traffic is increasing generally. Whether this is a function of globalization and having more trading partners is all up for speculation.
As for nefarious warnings, if we go by how many NORAD advisories and warnings they have been giving out, it's on a downward trend, and that could be because either Canada, the U.S., or both are able to detect the threat early enough that they can neutralize it before it has to become an advisory or a warning.
At the same time, our definition of a threat is expanding and changing. For example, one of the big innovations of NORAD was to track vessels coming from western Africa because of the Ebola threat. Ten years ago, we would never think of NORAD having that kind of a role. What it did though is allow Canada and the U.S. preparation time to come up with a plan of what to do if somebody lands in North America having been exposed to that virus.
Do we have an increase in incursions by foreign vessels with nefarious intent? I don't know. Based on the NORAD warnings and advisories, we are on a downward trend, so you could infer perhaps not, or we are getting better at detecting these issues earlier and neutralizing them before we have to hit panic stations.