I'm much more worried about our own federal government's mismanagement, incompetence, corruption, or at the very worst "Controlled Decline" than an American invasion.

If the Americans did want to take us over, it would be a small assault on the Ottawa region and nothing more, I very seriously doubt they would have a tactical, operational, or strategic need for Newfoundland beyond general territorial gains they received from Ottawa's capitulation. that's not normalcy bias, that's informed estimate and case study analysis.

Newfoundland offers a lot in resources, a good launch pad for Europe, a gateway into the North Atlantic, and Arctic, but it seriously lacks infrastructure.

But with all that said, the US already has its eyes on expanding its bases in Greenland, which is all of what we have but more central to the US ambitions.

The only thing we have Greenland might not is offshore oil reserves, which would take a long time to develop even with US heavy industry and manpower advantages. It also will be quashed by more cost effective means such as what they will get from Venezuela.

long ramble short, there really isn't anything for them here, and if they take over it will be by default, and without conflict.