Only if they're ODSTs or Spartan-III's, not II's or IV's.
I've actually had an idea for a Spartan-III and ODST based game for some time. FPS, of course, but it wouldn't be too unlike Battlefleet Gothic: Armada II in regards to a campaign.
You'd be based out of a
Point Blank-class ONI Prowler, operating behind Covenant lines. You'd have your overall objective for a theater, like say, blow up a Covenant Shipyard facility. But then you'd have smaller objectives, like destroying a methane refinery, retaking a deuterium distillation plant, convincing Insurrectionist holdouts to join forces, and things like that. Completing smaller objectives will make the Final Mission easier.
Since your Spartan-IIIs don't have MJOLNIR suits, and ODSTs can't use MJOLNIR anyway, your troops won't be like Master Chief or Noble-6. You'll have to move slowly and carefully, using the SPI Armor's photoreactive camouflage to carry out hit and run attacks, only engaging in open gunfights if there's no other option. Call in Baselard bombers as air support, but be aware that Banshees, Seraphs, Shade turrets, and AA Wraiths can shoot them down. Deploy Warthogs for better hit-and-run capability, or Scorpions for frontal assaults, but be careful...your air support and ground vehicles can
only be replaced if ONI thinks you're doing a good enough job to send replacements.
You'd also have a set amount of Spartan-IIIs and ODSTs to deploy for the entirety of a campaign length, with Spartan-III numbers only replenishing at set points in the story (to correspond with different Companies graduating), while ODST numbers replenish slowly after every mission.
But if you lose too many Spartans or ODSTs, you'll be declared combat ineffective and the Cole Protocol will be enacted on your Prowler, preventing you from returning to UNSC space and cutting you off from the UNSC's supply lines. You'll then be forced to deploy on the Final Mission with whatever you have left, basically making it a suicide mission no matter the outcome.
However, if you keep your casualties low, keep the Covenant's casualties high, and maybe even convince some Kig-Yar Pirates and Insurrectionists to help you out, succeeding in the Final Mission, ONI will congratulate you and give your Prowler access to better technology before sending you back out to do it all over again somewhere else.
Along the way, you'll run into Forerunner ruins that ONI wants you to check out, and you'll hear news of the war getting more and more dire as the story goes on...ending with your Prowler and whatever "allies" you've made being hastily recalled back to Earth when the Prophet of Regret enters orbit.
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I know this is a Gears of War thread, but you just made me remember this idea.