"Government shutdowns" are, among other things, wage theft from government employees.
In the Gingrich shutdowns of the 1990s, even active-duty military members' pay was delayed without compensation for up to three weeks. Yes, that's right: the Republicans literally stole paychecks from our soldiers and sailors just to stick it to Bill Clinton. (And maybe to give a little handout to their buddies in the payday loan business.)
More recent shutdowns have spared active-duty DoD, but still perpetrated wage theft against members of the Coast Guard and other defense-critical services. That was the case in the 2018-2019 shutdown, for example.
You can't convince me you care about border security if you don't fucking pay the Coast Guard.