When Budget Director Mick Mulvaney assumed the podium in the White House briefing room last week and previewed the administration's 2018 budget, Heather Block's fears quickly turned to outrage.

Block, a 54-year-old former international aid worker from Lewes, Delaware, listened with growing anger as Mulvaney promised to slice $72 billion from Social Security Disability Insurance (SSDI) and Supplemental Security Income (SSI) over the next ten years. The cuts are among $1.74 trillion in social welfare cuts proposed by the Trump administration, a sweeping plan that could kick people like Block off a program, known as SSDI, that keeps her financially afloat.

"Where are the morals of the people going after people dealing with Stage 4 cancer?" recalled Block, who has been on disability for five years after her cancer spread to her liver and lungs. "The people I know, like me, with advanced cancer — we've wanted to be in the workplace, but we don't have that ability now, so this is our income."

Disability insurance ensures benefits for American workers in the case of life-altering illness or disability. At the moment, roughly nine million Americans like Block depend on disability insurance, which includes an average annual benefit that hovers right above the poverty line. Supplemental Security Income, known as SSI, provides a basic standard of living for low income seniors and low income children and adults who meet the disability eligibility standard.

Mr. Mulvaney struggled to explain why exactly the administration was targeting disability benefits as part of its proposed cuts. But he strongly suggested that some beneficiaries are not actually disabled, and are therefore scamming the government out of money that could be spent elsewhere. Pushing beneficiaries back into the labor force, he argued, could save the government billions of dollars.

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"Shouldn't it be up to the government to make sure we can look folks who are paying the taxes in the eye and say, you know what, we did everything we could to make sure that everybody on SSDI is really disabled," Mr. Mulvaney said.

In briefings with reporters last week, while Mr. Trump was overseas, asked if people currently on SSDI would receive less as a result of this budget, Mr. Mulvaney responded that he hoped so – "if there are people who are getting SSDI who should not be," he quickly added.

The goal of the cut – the largest proposed cut to disability programs in the budget -- is to "test new approaches to increase labor force participation." The line item calculates that weaning disabled beneficiaries back into the workforce will save a total of $49 billion dollars.

Mr. Mulvaney did not elaborate on how new work requirements would be phased in or how the administration would weed out the "people who are getting SSDI who should not be getting it," as he put it, again suggesting that freeloaders are milking the system.

The Office of Management and Budget did not respond to a request from CBS News for additional information on the Trump administration's plan to promote workforce participation. Previous administrations have attempted, unsuccessfully, to implement programs to funnel disability beneficiaries back into work. The Heritage Foundation, an influential conservative think-tank, advocates for "time-limited" benefits paired with incentives to encourage re-entry, offering a clue as to what Mr. Mulvaney's plan may look like.

Mr. Trump's proposed 2018 budget also reduces retroactive disability insurance benefits from twelve months to six months prior to the date of application– resulting in $9.9 billion dollars in cuts and costing individuals an average of $7,000 in disability-related expenses, according to the Consortium for Citizens with Disabilities' Social Security Task Force.

Mr. Trump drew criticism from disability-rights advocates for his budget, which proposes major cuts to Medicaid and social safety net programs.

To disability insurance lawyers and experts, Mulvaney's presentation demonstrated a fundamental misunderstanding of SSDI, which does not cover partial or short-term disability, as the budget director claimed.

Rather, "Social Security disability beneficiaries are among the most severely impaired in the country," the agency's site says. "In fact, Social Security disability beneficiaries are more than three times as likely to die in a year as other people the same age."

But perhaps more troubling, experts say, is the way Mulvaney talks about disabled people.

"I feel like there's a lot of language being used that reflects attitudes that somehow people with disabilities are faking it or are slackers or just don't have the right attitude," Kate Lang, a senior staff attorney from Justice in Aging, a non-profit legal advocacy organization, told CBS News.

"Unfortunately there is a certain lack of sympathy or understanding of what life is like for people with disabilities, it seems," Lang added.

The Organization for Economic Development ranks the eligibility standard for federal disability benefits in the United States as being "one of the most stringent eligibility criteria, including the most rigid reference to all jobs available in the labor market" among member countries. Only Korea has a more stringent standard.

Mulvaney also did not mention is that "the best available evidence shows that the level of actual disability fraud is below one percent," due to pre-existing fraud programs already in place, according to a 2014 testimony from Carolyn Colvin, the Acting Commissioner of the Social Security Administration at the time. Other research from the Social Security Administration shows that only four in ten people who apply to SSDI are approved, and the process can take months and even years.

"All evidence is that the agency is making every effort to make accurate decisions and to make sure people get the right benefits at the right time," said TJ Sutcliffe, the director of income and housing policy at The Arc, a non-profit advocacy group for people with disabilities.

Based off of numbers from the Congressional Budget Office, The Arc estimates that about 946,000 SSDI beneficiaries could be kicked off of the program or be prevented from eligibility. They estimate that roughly 2.1 million people could lose access to SSI.

"Cutting people's basic living standards and ability to get by after experiencing the onset of a disability is not a way to help to get people to work," Sutcliffe added.

Also lost in the shuffle of President Donald Trump's trip overseas and the drama of a White House in disarray was another misleading claim: that "not a single thing in here touches Social Security retirement or Medicare," Mulvaney said of the budget proposal.

Mulvaney argued that SSDI was not technically a part of "mainline" Social Security, and therefore Mr. Trump was not breaking a campaign promise.

"If you ask 999 people out of a thousand, they'd tell you Social Security disability is not part of Social Security," Mulvaney stated.

Paul Van de Water, a senior fellow at the left-leaning Center on Budget and Policy Priorities, said Mulvaney's claims are politically expedient.

"I've worked on the issues for a long time, and we've always said that Social Security is a program that protects people against various risks of losing their earning capacity," Van de Water said. "Not least in cases where people lose their earning capacity because of a disability."

"The programs are completely integrated," he added.