When someone holds a different view, you can still agree to disagree and remain in a state of antagonistic harmony.
This is the resolution often taken by powerful opponents who each perceive there to be more to lose than gain from continuing the disagreement.
This approach tends to produce temporary holding positions that set the disagreement aside for a period before it re-emerges later when the balance of power changes.
If the argument continues, there are only two ways you can win it.
Either you must force your way, riding rough shod over your opponent, or you must invest the time to convince the other side that they are misguided, which in my experience takes a very long time, a lot of effort and works much less often than it fails, which is why so many give up.
This is the Putin strategy in Crimea.
HS2 is another case needing a sensible debate about efficacy, connectivity with other transport systems, return on investment etc but where one side of the argument has pushed ahead regardless of the a bad taste in the mouth and will eat away at the relationship and drive deep seated ingrained resentment.
To convince someone of your viewpoint or at least allow sufficient time for a full debate takes time and the deployment of one of two approaches. You must either present or heighten a fear in the minds of others, spotlight a belief and the attainment of a passion, or both.
Both approaches were evident in the Clegg and Farage debates last week but they came out in the exact opposite way to what you might have expected. Nick Clegg in speaking for the Grand Projet of the European Union was all about threats and fears rather than the realisation of the ideal of interdependent States working together for mutual benefit.
He stressed the 3-4m jobs that would be threatened, the economic dis-benefits of leaving, and the fear of crime and climate change not handled in unison.
Nigel Farage on the other hand, tarred with the brush of a Xenophobic Little Englander, spoke with absolute passion and energy about the Britain we could be, our role in the world and about how it made absolute commercial and social sense to control our borders rather close them.
Not a word to induce fear in the minds of the audience.
He was all about what we could once again be in the world.