Here is the short version.
There is a lot of concern about Russia and China working on hypersonic weaponry, primarily for anti-ship activities. China probably has enough money and technology to make this work, and they have set up a series of artificial islands around the South China Sea that contain military bases. The US has spent decades maintaining a vast collection of radar and space assets to track ICBMs and SLBMs anywhere in the world. The common trait of these missiles is that they exit the atmosphere en route to their targets. This makes them much easier to spot, and theoretically, makes them vulnerable to lasers or fast interceptor missiles.
The problem with hypersonic missiles is that they travel too fast for conventional aircraft interception, but too low for conventional ballistic missile interception. They would arrive with almost no warning from radar, designed to see things traveling at high altitude or low speed. Michael Griffin has stated that the only way to even see these hypersonic missiles is with a set of radar systems in medium to low Earth orbit, similar to the networks that provide GPS navigation or high speed satellite phone conversations globally. To intercept these missiles, the vehicles may or may not be space based. In fact, they probably would not be.
There is a second factor of what appear to be satellites from both Russia and China that can approach other satellites and manipulate them. They could be placing mines or jamming devices on board to be triggered in the event of a war. They could simply snip wires or crush components. Again, with legacy cold war satellites costing vast sums of money, there is very little defense against this form of attack. There must instead be either too many satellites to intercept, or a defense system to prevent those satellites from being sabotaged.
Existing government agencies are relatively moribund. They are no longer able to field brand new systems quickly without enormous waste in terms of time and money. NASA was very efficient up until it fulfilled its initial purpose of the moon landing. After that, it became another contractor game of how much money could be spent on how little work how slowly without the whole organization being shut down.
The US Military already spends more than NASA on space, and has done so for decades. This is mostly with the Air Force, but also includes such things as navy weather satellites, the National Reconnaissance Office, and so on. Interestingly, these spy satellites will remain separate from the new Space Force, which means that 90 percent of the assets being transferred to this organization will be from the Air Force.
Where Russia is concerned, there is some concern that this is a set-up. When Reagan announced the Strategic Defense Initiative, it was intended to leverage the US economy to end the Cold War without a fight. The US spent less than five percent of GDP on military efforts, whereas the USSR spent roughly 25 percent. The quickest way to win the war was to propose a plan to build a system that would invalidate the investments of the USSR that would not in itself be offensive. The Soviets had two choices – ignore it and fall behind permanently, or respond to it and go broke. SDI was only a $150 million research program at first. This is less than a cheap Mars probe mission. Yet it broke the stalemate of the Cold War.
Fast forward to 2018. Russia announces a series of wonder-weapons that could overwhelm existing US defenses. They include stealth fighters – but those have been largely cancelled because they were being built in cooperation with India, who have since pulled out of the program. They included an orbital ICBM that could be launched over the South Pole and hit the US from the side that lacks the DEW radar arrays for early warning. The problem here is that the launches can be seen from space (assuming our satellites are not sabotaged), and the actual weapons have been around since the 1970’s. A third item was a robotic submarine that would detonate a super-nuclear weapon under the ocean to wipe out all human life from the US East coast. This seems like a Dead Hand weapon, however, where the attackers assume the Russian mainland has already been deeply attacked. The fourth item were these hypersonic missiles, but those appear to be oversold. Test missiles have under performed. Another effort involved a nuclear propelled missile, but this seems to be a re-hash of a cancelled US program called Project Pluto from the 1960’s that was too dangerous to ever be tested, let alone used. In short, these appear to be Russian efforts to assume that the US government under Trump has forgotten what happened under Reagan and would fall for the same trick to spend itself into oblivion. It seems a bit ham handed as a strategy, and seems more likely to backfire into more boycotts and sanctions.
The real problem, then, is the Chinese effort. China has launched many tests of hypersonic missiles in an effort to neutralize the US carrier fleet. While Chinese fighters also seem to be oversold, the missile programs, ship programs, and artificial islands are quite real, as is the territorial ambitions in the South China Sea.
I suspect the Space Force will result in a fast, SpaceX-like effort to build radar satellites en masse, along with an effort to identify and disable any attempts to approach or intercept those satellites. That may involve blinding, jamming, or conversely intercepting the interceptors with radio frequency attacks. A modern radar satellite could certainly manage such an attack in terms of power and perception, if it were designed to do so.
A secondary benefit of such a system of satellites is that any sort of Malaysian airliner disappearance or stealthy 9/11 style attack with corporate or commercial jets would be largely nullified, because basically anything flying, anywhere in the world, would be tracked in real time.