International expansion is a subset of going global. In the end, the
two strategies may be the same; but starting out, it is important to
make the distinction.
One should hope that you start by considering your exit strategy or vision. What do you want to be when you grow up? What will be your legacy? Your goals and objectives, supporting your vision, may be described in a number of different ways, but should include a reference to creating value.
If this value is measured in terms of global potential, it may be most appropriate to say that you are going global. If, on the other hand, this value is tied to developing selected markets within specific time frames, international expansion may be a better description. Never mind that interim results may be exactly the same. It’s the perspective that matters most.
A global perspective tends to open up for more opportunities than a strategy to expand internationally. Often, international expansion is simply taking advantage of an opportuniy without a strategy (except, maybe, to go for the low-hanging fruits). Still, it may sometimes be appropriate to test the waters using an opportunistic international expansion strategy while working on a more comprehensive global plan.
Practically speaking, therefore, we do not make much of distinguishing among international expansion, global expansion, going global, foreign market development, and similar references, although your prespective may be important for your results.