I'm trying to write a novel about a German who vacations to the US with his family around 1905, but was that even possible at that time? I believe the US had good relations with Germany at the time, but that there were also some developing hostilities between Germany and France that I believe the US was mediating for. Would that have made vacationing unwise between the two countries? And would steamships be too expensive for say an upper middle class family from Germany to vacation to the US on?
Vacationing from Germany to the US in 1900 was rare, but not for the reasons you suggest. Most middle class people simply could not afford the crossing. Those who emigrated to the US from Europe spent all there life savings on this, and had to travel in pretty bad conditions, unless they were really rich.
Once I had an opportunity to read the diary of Ludwig Boltzmann (a famous physicist, professor in Vienna) who was invited to visit California by Stanford university in 1900 or 1901. This is a very informative and entertaining reading, and I recommend it to those interested in the recent history. US as seen by a European professor.
It is clear from the diary that for an Austrian professor, such a trip was a rare, once a lifetime opportunity. He crossed the US by train. Some of his most striking impressions were: a) a hotel room with a separate, private bath (!), and b) alcohol prohibition (it was local at that time, in the county where Stanford university is). As an average European, Boltzmann drank a glass of wine with his dinner during all his life, and claimed that otherwise he could not digest the food. So he crossed the Bay, bought a suitcase of wine, and had do drink it after the dinner in his hotel room with his door locked:-)
EDIT. I found it. Here is the reference:
His diary begins on p. 171.