Harper's administration, though losing focus on the issue by the end, was keen on enforcing the Canadian Internal Waters claim [1][2]. Trudeau, not at all [3].

To the detriment of Canadians, major players around the rest of the world consider these waters international waters, and on the international level, might (or the lack of response thereof) leads to facts-on-the-ground, as we've seen time and time again.

[1] http://www.theglobeandmail.com/news/national/the-north/myth-... [2] http://www.cbc.ca/news/canada/north/franklin-find-as-much-ab... [3] http://www.cbc.ca/news/politics/trudeau-obama-arctic-1.39059...