It has been 10 years since NBA left Seattle, a decision that did not disappoint and enrage only Seattle fans but fans around the country. Seattle was an amazing NBA city, they had one of the most vibrant teams in the league, played an amazing, attractive style of basketball and had fans that could be compared to any other.
As it happens so often, billionaire owners don't want to pay for a new arena by themselves but pressure local communities to pay for a large part or even the entire arena, which usually leads to increase in taxes to generate revenue for such an expense. After not being able to finance a new arena in Seattle, Howard Shultz and his partners sold the team to Clay Bennet (from Oklahoma City). The contract stipulated Bennet had to promise a "good faith effort" to keep the team in Seattle and build a new arena. He worked really hard at getting it for free (paid by the taxpayers) and after that failed he informed the NBA of the intention to move the team to, you guessed it, Oklahoma City. Who could've seen it coming?
With KD already on the team, they were moved to OKC, drafted Russ and the rest is history. Last night the Golden State Warriors played a preseason game in Seattle. On that occasion, KD went out on the floor in a Sonics jersey and told the fans it was good to be back in the city of WNBA champions Seattle Storm and that he hopes the NBA returns to Seattle for good.
It has been rumored for a long time now that one of the logical steps for a league in such expansion is to add a few more teams and everyone expects Seattle to be at the top of that list. Two groups of investors already expressed the ability to fund the entire project, the buy-in fee and a new arena with private capital, so the issues from the past are not an issue anymore.
The NBA usually is not very open about these kinds of plans, and understandably so. All we know so far is that the first possible time would be when a new TV deal kicks in (which is yet to be negotiated) so nothing specific is to be expected till 2025. Until then Seattle gets to enjoy The Storm and hope they will soon have the Sonics back as well.