I therefore believe that, similarly to recruitment telegrams, campaign telegrams should allow a button to be automatically appended to approve/withdraw approvals on/vote for/vote against the proposals being campaigned on. These should be sufficiently customisable to allow options for campaigning, countercampaigning, and at vote campaigning, for one or more selected proposals.

If this is done, it would have a number of benefits, some of which I will list below,
- This would also make the campaigning process more accessible to newer or less experienced delegates. Many would be unaware of how to otherwise approve a proposal; so such a feature would allow them to quickly approve a proposal per a campaign telegram, without receiving telegrams they might otherwise not understand. This leads into my next point.
- This would make campaigning and countercampaigning more effective, as delegates or other targeted nations would have a speedy way of approving etc a proposal, even if they are otherwise apathetic enough not to want to have to open a link and find the "Approve" button at the bottom of the page; or ignorant of the approval system, per my previous point. This would therefore discourage other tactics, such as quorum raiding, due to (1) being less necessary and (2) indeed less effective than in the status quo, due to this increasing the ability of proposals to quickly gather quorum. This also leads into my final point, regarding accessibility to newer authors.
- By virtue of making campaigning more effective in gathering approvals, including such a feature would make the campaigning process more accessible to newer authors. While the campaigning process is already relatively complex (such that it would still keep the barrier sufficiently high to require authors to care enough to get an API key or stamps), it would help authors garner approvals for their proposals without as much experience required on sending a proper or effective campaign telegrams. Sending "Please approve my proposal" tends to be more effective than a lengthy explanation for why one should approve the proposal; such a feature would allow newer authors to not have to worry as much about whether their campaign is effective, thereby encouraging the latter over the former.
Post edited to fix typoes. Discuss.
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Addendum. Some people in this thread have suggested that the proposal's text, or a link to the proposal, be also added to the telegram to minimise any "rubber-stamping" effect. I am not opposed to this; it would yield the same benefits listed above without letting poorer proposals through the quorum requirement. That said, I am personally unconvinced by the need for it; most proposals which are campaigned for fail quorum not due to their quality, but rather external factors such as countercampaigns or the campaign telegram itself, and poor proposals already get through the requirement relatively often; as do quality proposals fall from quorum.
If this were to be done, we should consider the clutter this would create in campaign telegrams -- in terms of having both an "Approve" (or "Withdraw Approval" etc) button, and a spoiler for the full text of the proposal. I don't think this would necessarily be a problem, but it is certainly something to consider. My idea is to have the buttons side-by-side, for example as follows,

Discuss.