For starters this whole immigration thing seems different.

Canada welcomes immigrant workers. Even fast-tracks their applications (within 2 weeks) to work in Canada.

This way Amazon can hire anyone, anywhere in the world (within reason) and they'll be able to move to Canada without any immigration issues.

In Canada, more than 60 percent of permanent residents are admitted via the economic class, most of them via the point-based system. Only one-quarter of permanent residents are admitted based on family ties.

vs

In the United States, about two-thirds of permanent residents are admitted because they are closely related to a U.S. citizen or a permanent resident. Less than 15 percent of permanent residents, including accompanying dependents, are admitted on the basis of employment.

Immigrants in the United States are three times as likely as natives to have not completed high school; in Canada, immigrants and natives are equally likely to have not completed high school.

So depends on type of workers they are looking for hq2. If they need mostly high skilled then canada might be better option.

Unless they create immigration issues.

The current administration in the US is actively anti-amazon. Primarily due to Bezos' ownership of the washington Post and its unflattering portrayal of Trump. If Amazon chose a Canadian city, the administration would likely go all in on attacking them. A hostile government is a tough thing to overcome even for a company as wealthy as Amazon.

Bezos sponsors research for the "10k year clock". Also, this HQ2 is going to be used for many years.

I doubt a 4 year administration worries them as much as you think.

Ability to hire international workers with ease would be huge.

Well, obviously and critically immigration for hiring from the necessary talent pool.

Well, for one, you wouldn't have the leader of the country constantly saying that your company's leader is a proponent of "fake news".