if hypothetically speaking we were to engage in a space battle with our current level of Technology we'll get hammered, as all the bad guys would have to do is bomb us into an oblivion from outer orbit and any attempt at defending ourselves(Tactical Nuclear Warheads,) would be intercepted before they even leave the Atmosphere.

If on the otherhand you are talking about a conventional Battle your best bet would be to hang your Flagship at a fair distance and send manned nuke Bombers in to take out the Bad Guys as it were. Kinda like mosquitoes to a Tiger