fusion powered relativistic quantum railgun that fires depleted uranium flechettes at 0.1% of the speed of light directly forward into the current and adjacent 256-worldlines so that it still hits the target if they are equipped with temporal armor or jump into another dimension

temporal armor is like modern reactive armor, except instead of exploding it utilizes the energy of being hit by a relativistic projectile to open a wormhole and travel backwards a second or two in time to avoid being hit

doesn't work against this though. it will just follow you right through time.

to escape being hit by this you'd need to jump several hundred worldlines across. this is possible but the world divergence can become pretty high on such big jumps so you might encounter strangeness

fleets of warships phasing in and out of existence shooting quantum railguns at each other, blue flares of light towering into the sky accompanying each dimensional jump

banks of supercomputers below deck calculating the worldshifts

The United Temporal States of America is a trans-dimensional federate state comprising of 36 versions of America in 36 adjacent worldlines. The electoral college now consists of each America casting one vote for POTTUS