To add, although the failed attempt at colonization and subsequent bankruptcy was a major factor in the Act of Union, it was not the only one. There was a 7-year gap lets not forget.
Of course the Scottish upper classes wanted in on colonialism, and realised joining England was the best way to cash in on this once the Darien Scheme failed and they went bankrupt. But this was also the time of the Jacobites and the Spanish War of Succession. It was acknowledged amongst both the Scottish and English upper classes that, in the context of global wars between European Great Powers - with a heavy backdrop of Protestant/Catholic animosity thrown in - that banding together was the best way to ensure strength, stability and a seat at the big table. Scots and English had already been jointly colonizing Northern Ireland under the authority of a joint monarch for the preceding 100 years, so teaming up to colonize even further-flung regions was hardly the greatest leap.
Long story short, Bannockburn and Braveheart are a complete irrelevance, but nevertheless vital to the idea of a backdrop of national victimhood that secessionist movements need to survive and thrive.
It is actually shocking how few people, on both sides of the English/Scottish border, actually know about the Act of Union and why the United Kingdom exists in the first place. You'd think it would be mandatory teaching in schools, but it isn't. In most countries it would be some sort of national holiday, but it isn't even that. I guess it ties in with our wider tendency to try and minimize our imperialist past. Iit doesn't suit either English or Scottish people to remember that political union and our modern political histories sprang about from a desire to protect a particular Protestant line of succession and colonize the world (plus a joint-hatred and mistrust of Catholics).
