For situations like this, I like to use devices with internal built-in antennas such as the Heltec MeshPocket, Seeed T1000-E, or RAK WisMesh Tag.

But all those devices are best used with a local repeater.

I have mostly resorted to using the tiny 4.5cm "glue stick" antennas. I carry my radio everywhere and any longer antenna ends up getting in the way enough to be a problem. The stub antennas supplied by Heltec (and almost everyone else) do surprisingly well for their size. But a whip like the one in your picture will more than double your coverage area. It's always a tradeoff.

Part of my reasoning is that I'm usually working through a repeater. I have one placed at a high point in my neighborhood. I have another that rides on top of my car. If my mobile is within reach of either, I'm reaching out a lot farther than the small antenna could manage by itself.

I have a jank setup with USC c + heltek testing out the range. It was fun.

I really like the idea and I want to get into meshtastic, so that I can communicate in case of an emergency.

Two questions:

1. is meshtastic the only protocol, or are there others?
2. does the community take the risk of an EMP seriously, or can I expect to be the only one with a working device after an EMP?