Republican Texas Gov. Greg Abbott this week signed an executive order that bars businesses in the state from imposing vaccine mandates for employees — though major companies like American Airlines (AAL) and Southwest Airlines (LUV) have vowed to flout the rule.

The executive order sets the state on course for a clash with the Biden Administration, which as soon as next week could finalize its mandate for large companies to vaccinate or regularly test employees, NBC News reported.

In a new interview, former general Stanley McChrystal — who led coalition forces in Afghanistan for two years and now heads a consulting firm called the McChrystal Group — weighed in on the political fight over vaccine requirements with support for a nationwide mandate, calling it an "entirely appropriate" policy in "a war against COVID."

"We have certain mandates," he says. "You must pay your taxes. You must serve in the military, if the nation is threatened."

"There are things we do as part of a covenant of being a citizen in the United States of America," adds McChrystal, who recently co-authored a book entitled, "Risk: A User's Guide. "There are responsibilities that go with rights."

McChrystal, whose consulting firm helped government agencies respond to the COVID-19 outbreak in Missouri and Boston, Massachusetts, sharply criticized U.S. leadership and messaging from the outset of the pandemic.

"We didn't communicate clearly," he says. "We sent mixed messages. We had a narrative that was undermined at times by counter narratives, first within official circles."

The call from McChrystal for a nationwide vaccine mandate extends well beyond the requirements currently put forward by the Biden administration, which has called for millions of government contractors to be vaccinated by Dec. 8.

Indonesia, Turkmenistan, and Tajikistan are among the few countries that have made the COVID-19 vaccine mandatory for all adults.

McChrystal, who graduated from the U.S. Military Academy at West Point in 1976, served a 34-year military career that included a stint as the commander of U.S. special forces and ultimately, a two-year tenure as the head of coalition forces in Afghanistan that ended in 2010.

Then-president Barack Obama accepted McChrystal's resignation days after a Rolling Stone article in which McChrystal and aides criticized senior administration officials.

Speaking to Yahoo Finance, McChrystal characterized the U.S. as a country at battle with the disease that should take the necessary measures to defeat it.