WIBTA if I put up a fence between my house and my neighbour?

Context: Ok, so my neighbourhood was mostly destroyed 15 years ago or so (do not ask how we don’t talk about it), and so we’ve kind of been rebuilding ever since. It’s not gone brilliantly for me – my overbearing father-in-law said he’d help out, which sounded great until it turned out that what he meant was taking away all the furniture that was still useful ‘to get rid of the clutter’, and now because he ‘helped’, he treats the whole house as basically his own, and just kind of camps out telling us what to do. I wouldn’t mind, but after a little too much vodka it gets pretty counterproductive and honestly just a little mean. The rest of the family is fed up with it.

OTOH my neighbour’s in-laws were… well, not necessarily ‘more chill’ but definitely ‘more rich’. Their house is now really, really nice – a high-quality build with modern appliances, and they must be earning plenty because they’ve just hired a gardener. The grass is LITERALLY greener.

I don’t approve of consumerism so it’s not that I’m jealous exactly, but I’ve found that my family is spending more and more time hanging out at the neighbour's place rather than our own house. Two of our children practically live there! I’m starting to think my wife is having an affair with the next-door neighbour – ok, yes my solid proletarian overalls are a little worn out, but that’s no excuse for sighing ostentatiously every time the neighbour comes home wearing that stupid American suit.

I’ve been talking it over with my father-in-law, who has gotten a bit miffed that his grandchildren are never home when he visits. He told me that he can get us a great deal on concrete, barbed wire and landmines – knows a guy, apparently – and it would just take a few days to cut off the neighbours completely. No more family desertion! Just one happy little community that isn’t distracted by buying the neighbours’ blue jeans and listening to their pop music.

I don’t know though – the last time I followed his advice on dealing with the neighbours, the noise pollution from air traffic got really, really bad.