I once interviewed the late U.S. Sen. Daniel Inouye about safety fears over nuclear waste dumps on Pacific islands.

“I don’t have the answer,” he said. “Who knows? In time, maybe somebody will invent a way to turn nuclear waste into ice cream.”

Inouye intended irony, but I worry the city has taken literally his concept of wishful fantasy in deciding the fate of the crumbling Waikiki War Memorial Natatorium.

Maybe if we avoid a decision long enough, somebody will invent a political solution that pleases all of the people all of the time.

Maybe Kaimana the seal pup will return and redevelop the pool and grandstand as a venue for spinning beach balls on her nose.

Or still my favorite: Maybe somebody will figure a way to encase the Natatorium in acrylic as a monument to municipal futility.

Mayor Kirk Caldwell, in his latest pronouncement on the long-neglected memorial for Hawaii soldiers who died in World War I, said doing nothing is not an option.

But in fact, doing nothing has been the city’s go-to option for nearly 40 years since the state shut down the Natatorium because of water quality concerns.

Former Mayor Jeremy Harris vowed to restore the swim stadium to its former glory, but couldn’t get it done.

Mayor Mufi Hannemann leaned toward razing the Natatorium to make a public beach, but it languished under study during his term and that of his successor, Peter Carlisle.

Caldwell proclaimed in 2013 that he was “committed 100 percent” to tearing down the pool and grandstand to create a beach park, leaving only the Natatorium’s archway as a war memorial.

But it turns out that a 100 percent commitment on the Natatorium is about as solid as an “on time and on budget” promise on rail.

Caldwell said last week the city is now studying a third option — partial restoration that would keep the grandstand, but replace the enclosed pool with a more open swimming area surrounded by a “perimeter deck.”

The only constant is rising costs.

In 1998, Harris pegged the cost of a full Natatorium restoration at $11 million; now the city estimates $40 million to $60 million.

The U.S. Army Corps of Engineers said in 2009 it would cost between $1.7 million and $6.3 million to tear down the Natatorium and restore a beach, depending on the size of the beach.

This cost is now estimated at between $20 million and $30 million, the same as the proposed partial restoration.

Caldwell said he hopes to start work on one of the options before he leaves office at the end of 2020.

But with the final environmental impact statement another 18 months away, funding tight and public opinion still sharply divided, that’s about as likely as crumbling concrete turning into Spam musubi.

Reach David Shapiro at volcanicash@gmail.com.