Some of us might recall a quip made famous by former Vice President Walter Mondale as he competed for the Democratic presidential nomination in 1984.

His chief foe that year was U.S. Sen. Gary Hart of Colorado. The two of them squared off in a debate and Mondale turned to Hart and asked him: Where’s the beef?

The question has become something of a punch line.

I think it’s fair ask another challenger for the Democratic nomination essentially the same question. It ought to go to Sen. Bernie Sanders of Vermont.

Where is the beef, Bernie? Where are your constructive solutions to what you say ails the country?

I’m not hearing them.

Sanders captured two Democratic caucuses today, in Washington and Alaska. The frontrunner for the party’s nomination remains Hillary Clinton.

I listened last night to quite a bit of Sanders’s rally in Seattle. He stood at a lecturn in the middle of Safeco Field and kept saying what he’s been saying all along.

The campaign system is corrupt and he wants to bring public financing to presidential elections; the top 1 percent are getting richer while the rest of America is suffering; he wants to provide free college education for every student in America; he says every American is entitled to “universal health care.”

OK. Fair enough. I get the message.

The question: How are you going to make any — let alone all of it — a reality?

It occurred to me this afternoon while visiting with a friend: Sanders sounds a little like Donald J. Trump. Yes, he’s tapping into voters’ anxiety, anger, fear and frustration, just like Trump.

The difference, though, lies in the tone and tenor of his remarks … not to mention the tone and tenor of his response to criticism.

As I listen to Sanders, though, I keep hearing the same refrain.

Wall Street is bad. The political system is corrupt. Wages are unequal.

What is the candidate going to do — precisely, I must ask — to fix it?

Where, Sen. Sanders, is the beef?