By Elizabeth Warren, Reader Supported News

My brother David has always had the special spark in our family.

Like our two older brothers, David served in the military. When he got out, he started a small business – and when that one didn’t work out, he started another one. He couldn’t imagine an America where he wasn’t living by his wits every single day.

Year after year, my brother paid into Social Security. He never questioned it. He figured he was paying so that he – and a lot of other people – could have a secure retirement.

Today my brother lives on his Social Security. That’s about $1,100 a month. $13,200 a year.

I’m telling you my brother’s story not because it’s unusual, but because it’s like the story of so many other people. I can almost guarantee that you know someone – a family member, friend, or neighbor – who counts on Social Security checks to get by.

That’s why I was shocked to hear that the President’s newest budget proposal would cut $100 billion in Social Security benefits. Our Social Security system is critical to protecting middle class families, and we cannot allow it to be dismantled inch by inch.

The President’s policy proposal, known as “chained CPI,” would re-calculate the cost of living for Social Security beneficiaries. That new number won’t keep up with inflation on things like food and health care – the basics that we need to live.

In short, “chained CPI” is just a fancy way to say “cut benefits for seniors, the permanently disabled, and orphans.”

Two-thirds of seniors rely on Social Security for most of their income; one-third rely on it for at least 90% of their income. These people aren’t stashing their Social Security checks in the Cayman Islands and buying vacation homes in Aruba – they are hanging on by their fingernails to their place in the middle class.

My brothers and I grew up in an America that invested in its kids and built a strong middle class. An America that allowed millions of children to rise from poverty and establish secure lives. An America that created Social Security and Medicare so that seniors could live with dignity.

We can’t chip away at America’s middle class and break the promise we make to our seniors.