The record-breaking government shutdown has exposed a deepening rift between the head of the Department of Veterans Affairs and the union representing many of the VA’s employees.

Secretary Robert Wilkie, a Trump nominee, sent a letter to the president of the American Federation of Government Employees on Monday accusing the union of “stereotyping” veterans as victims in the 24-day partial government closure.

While no one deserves to be furloughed or required to work without pay, the union has been quick to point out during the shutdown that the federal government employs a disproportionate number of veterans. Nearly one-third of the civilian federal workforce has served in the military, although the percentage varies greatly from agency to agency.

Some 800,000 federal workers have gone without pay since Dec. 22. According to Stars and Stripes, an estimated 155,000 veterans work in agencies affected by the shutdown, 50,000 of them with a disability rating.

The comments that prompted Wilkie’s letters came from Edward Canales, a local AFGE president and a union liaison officer for veterans. Canales is an Army veteran who served in Operation Desert Storm and is “a 100 percent disabled veteran” due to combat injuries, according to his union bio. He told ABC News last week that he had fielded calls from veterans who work for the government and were distraught over how to pay their bills during the shutdown.

“If this shutdown does not stop, we are going to have fatalities,” Canales said, according to ABC. “We’re going to have suicides.”

Wilkie apparently felt that remark was out of bounds. In a letter the VA made public on Monday, the secretary said that the union was promoting the stereotype of “veteran as victim.” He didn’t buy the idea that stress brought on by the shutdown could lead to a veteran’s suicide.

“[T]he notion that most Veterans are so fragile from their service that the slightest hint of hardship can push them to the brink of mental breakdown or even self-harm is preposterous, which is why Veterans and Veteran advocates are continuously fighting this shopworn canard,” Wilkie wrote.

Wilkie called on AFGE’s national president, J. David Cox, to apologize. Cox declined and instead fired back at Wilkie, saying the Trump administration “has been one of the worst on record for our country’s heroes.” He also said that White House officials don’t grasp the financial stress the shutdown is causing.

“The President and his cabinet have left [veterans] out in the cold, forcing them to work without pay and subjecting veterans and their families to the uncertainty of not knowing when or where their next paycheck will come from,” Cox said in a statement on Monday. “Financial pressures experienced by working people are apparently not something this administration either understands or cares about.”

The current shutdown became the longest in U.S. history on Saturday. The president, who said he would be “proud” to close the government over border security, has demanded that Congress provide $5.7 billion for a wall along the southern border that he used to claim Mexico would pay for. Democratic lawmakers have refused.

Roughly a quarter of government functions have gone unfunded, leading agencies to furlough 380,000 workers and require another 420,000 “essential” employees to work without pay. Democratic leaders in the House have moved several bills that would reopen agencies while Congress and the president negotiated over the wall, but Trump and Republican leaders in the Senate have declined to take up the measures.

The House and Senate passed a bill last week approving backpay for government workers affected by the shutdown, as has been done in past shutdowns. But the workers won’t get paid until the government reopens and payrolls are processed. Trump also has to sign the legislation.

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