"Economically viable" is not a concept that even applies here. There is no profit to be extracted on Mars besides raw resources, and it will basically never be

"Economically viable" is not a concept that even applies here. There is no profit to be extracted on Mars besides raw resources, and it will basically never be profitable to ship raw materials between planets with chemical rockets. Any hypothetical money to be made on a Mars colony will take generations to become apparent. However, the technological advances required to build a Mars base and put humans there is within our grasp today. The developments associated with such a program would be of incalculable value to humanity, but are not directly monopolizable and monetizable in the immediate term. So, no. It will never be economically viable to go to Mars because that question makes no sense. It would make economic sense to invest in asteroid mining because there are returns to be seen within your lifetime. There will be no such returns from any planet-based colony for a long, long time.