The theory runs that if you give ground on A that B will fall and then C and D and so on. The Domino Theory is used to resist change and rally support by fueling fear. The theory is used to support the status quo, even a status quo that abuses others. Rather than engaging is discussion and the seeking of understanding by building upon common, the proponents use the theory to build hardened silos that resist dialogue.
A recent example is the stalling of proposed gun law changes in Virginia that arise out of the VATECH shootings. While the defeated legislation can return for a vote in a year, it has been defeated. The proponents of the proposed changes have noted that the modest modifications are not intended or designed to keep the guns out of the hands of law abiding citizens. One of the changes calls for background checks to be conducted at gun shows to help keep guns via this route out of the hands of those with criminal records or with mental health issues. The NRA strongly opposes background checks in any form.
The NRA argument runs that if they cede to background checks that it will set in motion a chain of events that will remove guns from all citizens and to then to a police state. The organization has gone on the record saying that nothing should be in place to hinder criminals purchasing guns at gun shoes or gun shops. When one reads their arguments carefully they are essentially arguing that it is the citizenry owning guns the keeps the nation from sliding into a totalitarian police state. Hence, freedom according to the NRA is not found in civil discourse, in free elections via the ballot box but in the arms that people are permitted to hold. The NRA therefore has redefined the essence of democracy.
We have seen the Domino Theory use to support slavery, segregation and racism. It has been used in the church to resist modern music and changes in worship style. It has been used to beat down those who question traditional teachings.
The enemy of the Domino Theory is mutual dialogue, seeking common ground and the realization that modification of viewpoints does not lead to the destruction of the whole as the Theory would suggest.