Jim Lo Scalzo, Associated Press
President Donald Trump leaves after speech to a joint session of Congress on Capitol Hill in Washington, Tuesday, Feb. 28, 2017.

President Donald Trump’s speech struck a tone of unity and optimism while advocating for the unique mixture of political positions that fueled Trump’s rise to the White House. But last night’s joint session of Congress is notable not just for what Trump said, but for what he didn’t say.

To President Trump’s credit, he focused a great deal of attention on deregulation, repealing and replacing Obamacare, reforming immigration and cutting spending while also increasing it for military and infrastructure. These are all important issues that will undoubtedly receive a public hearing through the legislative process.

Yet Trump largely avoided discussion of the two-thirds of government's spending that flows out of Washington on autopilot through Social Security, Medicare and Medicaid. These represent some of the most popular programs in the country.

But if entitlements are not reformed, they might end up drowning the nation in debt.

When Social Security began in 1935, the life expectancy for women was 62 years, while the life expectancy for men was only 58 years. Ten years after Social Security was instituted, there was an average of 41.9 people in the workforce paying into the system for every person receiving Social Security benefits. Today, life expectancy for men is 84.3 years, while the life expectancy for women is 86.6 years, and there is an average of only 2.9 workers for each retiree.

To sum up, we’re living far longer than we used to and collecting far more benefits with far fewer people paying for them. That is not a sustainable system. On its current trajectory, Social Security cannot survive.

And Medicare is in even worse shape. Medical costs continue to rise far above the rate of inflation, and our aging population is making increasing demands on a trust fund that the Congressional Budget Office predicts will be insolvent within a decade. The president spoke of repealing and replacing the Affordable Care Act, but he was entirely silent about what could be done to keep Medicare from collapsing.

The problem is that politicians who try to address these problems are usually punished at the ballot box because some characterize even the mildest reforms as draconian assaults on America’s senior citizens. President Trump, consequently, has promised not to touch entitlements. It’s little wonder why he didn’t mention them last night.

That may make for good politics, but it’s a destructive policy. Thankfully, there are Republicans in Congress, including House Speaker Paul Ryan, who recognize the looming crisis and are willing to act to avoid it. Although overall President Trump struck a laudatory tone last night, when it comes to entitlements, he needs to not only to speak to members of Congress, but perhaps listen to a few of them as well.