Why the US Marine Corps gave up its own tanks

The Marine Corps shifted tank responsibility to the Army because its expected Pacific island role favors other armored vehicles and naval fire support, not because armor has become universally unnecessary.

Question

Did the US Marine Corps eliminate its tanks because modern amphibious forces no longer need them?

Short answer

No; it shifted tank provision to the Army and tailored its own force to island warfare, where naval guns and other armored vehicles can cover many expected tasks.

Notes

Giving up an organic tank corps does not mean tanks are never needed. The Marines can draw Army tanks when an operation requires them and continue to pursue armored personnel carriers and related vehicles. For confined islands in a western Pacific campaign, ship guns can engage enemy tanks while lighter formations exploit the limited terrain. This logic is theater-specific: forces operating beyond enclosed islands still need heavy armored capability.