Hard evidence of bribery or extortion has not been presented,
No evidence of bribery or extortion has been presented. Hard or otherwise. None. Zip. Nada.
but the obstruction article is valid.
Uh, no. There is nothing valid about witchhunts designed to create evidence where none exists. At no time should anyone cooperate with an empty prosecution - empty in both evidence and charge. Besides, no one can be compelled to testify against oneself. At least that is what the Constitution says, not that Democrats give a rip about the Constitution.
Ask yourselves whether you would want a President Hillary impeached for ordering her staff to defy congressional subpoenas.
No. I would want her impeached for breaking the law - something Trump has not done. Besides, it is not within the power of the Legislative Branch to issue subpoenas without Judiciary approval. The ends do not justify the means. If Hillary gets caught breaking the law (like she did with her disclosure of classified material), then a case for impeachment could be made. But that doesn't mean she or any of her staff can be forced to testify by Legislative edict. That is not the way our system of government was set up. And if she doesn't get caught breaking the law, then she shouldn't be impeached, no matter how much one despises her Presidency.
Had some of them cooperated, it may have edified the president's standing. Or they may be helping the White House with a coverup. We'll never know in part because of the obstruction ... which, if there was nothing to hide, was damn stupid.
The only coverup here is the collusion by Democrats to overturn an election. Think about it. The key prosecution witness that launched this entire effort has not uttered one word before Congress in this entire affair. Not a single word. Yep, there's a coverup all right. And it is coming from the same people who have openly stated that the only way to defeat Trump in the next election is to impeach him.