Apple can agree to invest 500B to build a factory, but they don't have to actually do it.

Building a factory takes years, and a big chunk of that happens long before you actually start work on site.

You gotta find a site, work with local govt to negotiate servicing, environmental report (there's a couple years, and potentially a couple go-arounds right there.)

So there can be lots of activity, lots of progress reports, lots of optimism, for a decade or more before any real money has to be spent.

Ultimately Apple et al can "agree" to anything, the president can have his "big win" and things can carry on just as before.