[yyyk]

A vote by mail loses the guarantee of secrecy (someone could check your mail and ensure 'consequences' for your vote, or even for voting in general), safety (someone could have coerced your vote, and because it was by mail they could verify 'your' vote was what they decided it to be), intelligent decision making (a mailed vote is mailed in advance, something could have changed by election day. This actually happens quite often, especially in primaries) and election integrity (someone in the mail could have messed with your vote).

Mailed votes are just a bad idea. The simpler and better solution is to have the US federal elections run by a federal non-political commission + a federal voting holiday. Disabled people could use mobile election vans and/or a proxy-vote system like in the UK but limited to them (very imperfect; but safer than a mailed vote, since the proxy's vote is still secret).

[fsh]

Agreed, voting by mail shares a lot of fundamental problems with online voting.

Most countries in Europe have no problems at all organizing fair in-person elections.