That may be more likely a priori (after all, much "military" funding is in fact a convenient way for the government to fund R&D without huge budget fights in Congress).
But, ICF is simply not a viable way to produce fusion power, it is far far far too expensive to operate such a device. So, we can only conclude that they are either deluding themselves, or they are in fact doing fusion weapons research (or, at best, simply fundamental theoretical research into how fusion works) - since the same kinds of conditions or forces are what happens inside a fusion bomb.
But, ICF is simply not a viable way to produce fusion power, it is far far far too expensive to operate such a device. So, we can only conclude that they are either deluding themselves, or they are in fact doing fusion weapons research (or, at best, simply fundamental theoretical research into how fusion works) - since the same kinds of conditions or forces are what happens inside a fusion bomb.