[Boston Dynamics]...promised in an open letter co-signed by five other robotmakers earlier this month that it won't allow its machines to be "weaponized" by either itself or its customers.

While I admire the principle behind what they're doing here, it seems completely impractical when it comes to military hardware.  If there's a strategic advantage to be had by weaponizing any technology and there's not an international agreement banning it, someone will do it.  If the advantage is big enough (i.e. nukes) some countries will develop the tech even despite international bans.

If Boston Dynamics succeeds in keeping this out of US & Western militaries, it just means that China, Iran, Russia and others will develop and have access to weapons that we don't.  They certainly aren't going to back away from it just because there's a US patent in their way.

Once a technology that could be used for military purposes is invented, it seems to me that it is practically impossible to prevent it from being weaponized.