It can be.
At the present level of space development, obviously it is not. Perhaps the commsat sector, or the GPS sector is close to profitable. The science missions are nowhere near self-supporting, it's all government with a little university thrown in.
The sectors of space development that can be profitable are a few industrial sectors and space tourism/Hollywood, none of which are developed at all. Such a sector must reach a certain stage of development before it can begin to break even or get ahead.
For example, Space Adventures is building a mini- Buran in Russia for suborbital tourist flights, ticket $80,000 each. They are years from first launch, and years from profitability.
Space mining is an area I have studied. It can be developed to the point of profitability, and the market already exists. But the investment is large and the time to first paycheck is fairly long.
Space power satellites is something China wants to work on. This could be made to work and pay its own way, maybe more. So far nothing has been done away from the drafting tables.
Space farming is another possibility, but I consider this to be much more difficult in a business sense than space mining; space farming is coming sooner or later, but commercial space farming is a long way off.
A moon settlement can be created, but it won't be commercial. It might be made self-supporting, but not a money-maker.
These are just a few possibilities. Space mining is economically possible now, the rest won't be until later. Tourism/Hollywood can be done anytime someone builds a ship, but profitability is a different question.