bjlockie I can understand the sentiment, and it is likely exactly the sort of thing that Donald would do. To me, however, that is precisely the reason that we should not do it. We should not ever let him pull us down to his level, even considering @Hydraglass's justifications. @Avernar explained it very lucidly.
Still, buying equipment essential to our national defence from them in this climate seems unwise, to say the least. I'd say terminate, pay, move on. Then, we should still be in good standing globally (except maybe with Donald, though that ship seems to have sailed already), and even Lockheed Martin would be foolish to avoid dealing with us in the future, unless they don't like contracts, money and satisfying shareholders.
Based on our national experience, the United States doesn't have a great track record with these projects, delivering on their promises or serving the collective interests; NORAD and NATO be damned. They use "compatibility" and "inter-operability" to manipulate others into buying their junk, that subsequently fails to deliver; the Bomarc/SAGE system was but one major example. Especially now, buying from them for our defence seems about as smart as hiring a hungry cat as a security guard for your birdhouse.
This project is substantially over-budget and late, and has had its share of glaring failures. Furthermore, it barely met our requirements to begin with. To me, this seems like another instance of our southern neighbour trying to use us to help defray the unreasonable costs of another mostly-failed project. We have better things to do with our limited resources than subsidise their failures.