In the US, Obama's administration was publicly against "boots on the ground" since it was largely unpopular in "liberal" circles after Bush's "War on Terror". Instead, Obama's administration increased drone based missions to do the violent bidding of the owning class.
"Liberals" may talk a great game about immigration reform, ending prisons like Guantanimo, net neutrality and protecting consumers from the owning class. When action is required "liberals" continue to advance the owning classes agenda using means that do not look bad to their base. Japanese internment camps were an executive order by a "liberal" President.
This is US centric, but the issues are inherent to Liberalism. Historical non-fiction is a genre of book.
Here's both from an Anarchist perspective.
We keep us safe. Access and training is required for defense of the community.
Vaccines should be shared with humanity. Vaccine schedules are decided by consensus of the community.