Is Russia developing a space-based nuclear weapon? Why is the US so concerned?

The White House announced on Thursday that Russia is in the process of developing a space-based anti-satellite weapon, which worries the United States. But they said it's not an immediate danger to people on Earth. This news comes after US lawmakers warned about a serious threat to national security without giving details. Moscow has refuted these claims, labelling them as "malicious" and "unfounded," and suggesting they are a tactic by the White House to push through a stalled multi-billion-dollar Ukrainian war aid package in Congress. Thought the exact nature of the weapon — and whether it actually exists — is…