3 realistic host cities for NBA expansion - and 3 long shots

The topic of NBA expansion seems to come up every few months, but commissioner Adam Silver's response has been consistent: The league is not in expansion mode right now. And that makes sense - with an even 30 teams, there's little sense in expanding by one. Anything more than that also runs the risk of diluting the talent pool.

Certain NBA-free markets stick out, however - nowhere more so than in the Pacific Northwest. And further down the road, Silver has left the door open to the idea of overseas expansion - although serious question marks like time-zone impact haven't been discussed publicly.

Here are six cities that could be expansion candidates if the NBA does decide it's time to grow. The first three are at least somewhat realistic contenders:

Seattle

Metro market population: 3.7 million

Pros: Seattle NBA fans were robbed of the SuperSonics in 2008, and since then, The Emerald City has been generally considered the first choice in expansion or relocation scenarios. The Kings almost moved there in 2013, and the Bucks used the city as leverage in 2015.

Cons: An arena war is ongoing in Seattle between billionaire hedge-fund manager Chris Hansen and former longtime sports executive Tim Leiweke. Hansen wants to build an NBA-first arena, while the latter's prepared to remodel the city's venerable KeyArena - and apparently prioritizes getting an NHL team as a tenant. Seattle mayor Ed Murray is on record as a proponent of the KeyArena plan.

Mexico City

Metro market population: 20.4 million

Pros: Mexico City is one of the largest cities in the world, and for that reason, Silver admitted the NBA is looking more closely at its long-term viability as a league market.

Cons: That viability is a long way off. In addition to economic challenges, Mexico has an astronomical rate of violent crime. In the past, some NBA players balked at playing in Canada. How would they feel about Mexico?

Las Vegas

Metro market population: 2.3 million

(Photo courtesy: Getty Images)

Pros: A brand-spanking new facility, T-Mobile Arena, opened on the Strip last year. It's already hosted NBA and Team USA exhibition games, and Vegas has a strong basketball culture, with its summer league and local support of UNLV.

Cons: The NHL beat the NBA to it, and the NFL's slated to move in nearby in the next few years. While there are always investors with money, there's real concern about whether the Vegas market will already be saturated with professional sports by the time basketball could arrive, given the city's population and economy.

Here are three more potential NBA destinations that should probably be considered long shots:

Kansas City

Metro market population: 2.1 million

Kansas City opened a state-of-the-art arena, the Sprint Center, back in 2003, and has been waiting for a permanent professional tenant ever since. No NBA or NHL franchise has come close to moving there.

Vancouver

Metro market population: 2.4 million

With the loss of the Seattle and Vancouver franchises, the Cascadia region that used to have three NBA teams now only has one - the Portland Trail Blazers. Canada's third-largest city lost the Grizzlies in 2001, in large part due to a lack of corporate support. Vancouver has grown rapidly since, and now contains some of the most expensive real estate in the world.

Louisville

Metro market population: 1.3 million

A local councillor claimed in January that he was "working on" bringing an NBA franchise to Kentucky's largest city. While Louisville has a rich college basketball history with the Cardinals, the city is likely too small to be considered.