Fairly senior dev, US citizen here (20 years experience).
After what I've seen this past year, but more the past month, I will work for peanuts for a path to citizenship in Canada. US in 5 years is not a place I want to be, looking into all options and very serious.
Starting a business in the USA is often far more lucrative, but people usually still incorporate in both countries for tax and liability reasons.
Things like the Canadian youth tax-credits also mean anyone over 28 gets pushed down the list for entry-level positions. The US is far easier to find a reasonable job, and the cultural tradition of entrepreneurship is far better. =3
Not saying anyone's right or wrong but the idea that, should America go psycho, Canada would somehow be okay is a pipe dream. Canada is essentially an outpost of the United States. Yes, I have Canadian family (even old stock "Loyalist" Canadian family) and they all feel the same way.
People need to be real.
If you actually want to be able to declare independence from America you'd need citizenship in a country with actual nuclear capability. France, the UK, China, etc
On the military angle, I'd much rather live in a country without nukes. But I'm willing to kick the nuclear blackmail risk can down the road, my own government's threats are way more immediate.
People have been saying they are moving to Canada for decades due to whatever recent events, statistics say otherwise.