For Trump's first month, his approval numbers are about the same as much of Obama's second term.
There's two schools of thought on Trump's current approval ratings.
Some say he's starting his Presidential term at historical low numbers and now has zero cushion and will only go down from here.
Others say, we're so polarized these days 44% is the new normal. Also Trump has done zero outreached to improve his numbers, but he does have a solidified hardened base of about 35% that will stick with him even through an impeachment trial for treason as long as the economy is perceived to be doing good.
Personally I think both thoughts have truth to it. As some already mentioned in this thread, Trump does have a hardened base but if they start feeling some new hardships under Trump, then you could start to see his base liquify. That's why repealing Obamacare is so dangerous for Republicans. A large portion of Red states are the beneficiaries of Obamacare and if their healthcare benefits erode under Trump, then that could cause Trump's numbers to implode even among Trump loyalist.
Also, outside of a presidential campaign, it takes time for approval numbers to go down. Not everyone is dialed into politics all the time, so it may take 12-18 months of consistently bad news and mistakes for it to reflect in Trump's overall approval rating. And while 35% has completely hardened for Trump, it's pretty clear 50-55% have hardened against Trump over the past month. Democrats already hate Trump more than George W. Bush and many Independents are already having buyer's remorse.
Progressives mostly fell asleep during the 2016 election. But the sleeping giant has been woken and it looks like it's going to be a blood bath for Republicans in the 2018 mid-terms. It's why you got guys like Darrel Issa calling for independent investigations. He sees the impending wave. And almost no one at this point feels Trump has a shot at being re-elected.